Find and fix the causes of the error "Purchase not registered" of the Android application on Tomcat (Part 3)

We are a DTC wellness brand, selling dietary supplements to the US market via subscription, and the app serves as an assistant that gets to know the customer better, collects their data for further mailing, which will remind them to take the supplements (AM/PM), mark intake in the calendar, and show progress. The app is gamified with achievements, personalized push notifications with compliments for each day, and pleasant predictions (like in fortune cookies). Backend / data — Firebase 1. OnboardingThe user opens the app — the first screen with the SHE·8 logo, a photo of a girl, and the text “Your daily reset begins with you.” At the bottom, there is a button “GET STARTED,” below it a link “Already have an account? Log in.”2. RegistrationAfter pressing “Get Started,” a survey begins with 5 steps (Step 1 of 5). The first question: “What is your main goal?” — options: Better Sleep, Less Stress, More Energy (selected), Better Focus. The “NEXT” button leads further through the steps.3. Reminder SettingsAfter the survey, the user sets the time for two reminders — morning (08:00) and evening (20:00), with an explanation that the app will remind them to take the capsules. The “SAVE” button.4. Morning ResetWelcome screen: “Good morning, Sarah ☀️,” “Day 8 of your Reset,” an illustration of capsules with a glass of water, instructions to take the morning capsules. The “I DID IT ✓” button — the user marks completion.5. Late Check-in / Evening ResetDark screen with the moon — “Evening Reset,” text “It’s time to relax and take care of yourself.” The “I DID IT ✓” button.6. Reminder if Evening Intake is MissedIf the user forgot to check in, a screen appears “Hey, Sarah! ” with a tired emoji icon, text “You haven’t marked your evening intake yet” and two buttons: “Yes, do it now” (main) and “Later” (secondary).7. Main DashboardAfter onboarding or logging in, the user lands on the main screen: “Hi, Sarah! ,” a motivational phrase, a block “Current Streak — 8 days ” and a circular indicator “Progress — 80%.” At the bottom, the navigation: Home, Progress, Calendar, Me.8. ProgressTab “My Progress”: current streak (8 days), “Days completed 8/10” with a progress bar, weekly tracker (Mon–Sun with marks completed/missed), overall “Overall progress — 80%.”9. CalendarTab “Calendar”: monthly view (June 2025), days marked by color — completed (green), today (blue), missed (red). The user can click on a specific day.10. Day DetailsWhen selecting a day (June 8, 2025), a detailed screen opens: status of morning (08:15 ✓ Completed) and evening (20:05 ✓ Completed) intakes, plus a “Daily note” field with the user’s personal note.11. Your ResultsScreen “Your Results” — comparison of metrics “Before” and “After” (Energy, Sleep, Stress) in the form of progress bars that visually show improvement. The “SEE MY JOURNEY” button.12. MotivationScreen “Daily Motivation” with a background photo and an inspiring quote: “Small daily actions create big changes.”13. AchievementsTab “Achievements”: list of earned rewards (First Step, 7 Days Streak, 10 Days Streak) and the next goal (“Next achievement — 30 Days Streak,” progress 8/30).14. ProfileTab “Profile”: avatar and user name (Sarah), list of settings — Personal Information, Reminders, Notifications, Subscription, Help and Support, and the “Log Out” button.

We will go through each point. Technical task for the development of a mobile application for a sushi delivery service A mobile application (Android and iOS) needs to be developed with functionality as close as possible to the website 911sushi.com.Main requirementsIntegration Full integration with Poster POS. All orders must automatically go directly to Poster. Use of the existing customer base in Poster. Automatic application of personal discounts for guests already set up in Poster.User authorization Registration and authorization. Login by phone number (or another modern method of authorization). Saving order history. Personal discounts and promotions for the user.Menu Viewing categories and products. Detailed information about items. Ability to add products to the cart. Selection of modifiers and add-ons (if needed).Cart and order placement Selecting a delivery address. Saving multiple user addresses. Selecting a city. Selecting delivery time or "as soon as possible". Displaying delivery costs depending on the zone. Support for delivery zones with the ability to edit them.Admin panel A convenient admin panel is required with the ability to: Edit the menu; Add and remove items; Change prices; Change categories; Manage promotions; Create and send promo codes; Set limits on the use of promo codes; View statistics.Promotions and marketing Provide the possibility of: A promo code for the first order; A bonus or discount for installing the app; Creating promo codes with a limited number of uses; Mass mailing of promo codes to users; Conducting promotions without the need to update the app.Analytics Detailed statistics are needed: Overall app performance statistics; Statistics for each menu item; User conversion; Number of installations; Number of completed orders; Average check; Repeat purchases; Delivery analytics by addresses; Selection of the 100 most popular delivery streets; Other key performance indicators for sales analysis.Information sections The app must include: Links to social networks; Contacts; A map with the location of the establishment; Information about the company; Delivery and payment conditions.Application performance requirements Fast and stable operation; No freezes or critical errors; Modern and user-friendly interface; Support for current versions of Android and iOS.Design There is currently no separate design. The existing website 911sushi.com can be used as a basis. All necessary materials have already been prepared: Logos; Brand colors; Menu; Brand book (if available).Phased implementation I consider phased development:Phase 1 Basic functionality; Integration with Poster; Menu; Cart; Order placement; Authorization; User account.Phase 2 Promo codes; Promotion system; Analytics; Statistics; Additional marketing tools; Other functions that may arise during the project development.Additional conditions After the development is completed, a 30-day testing period must be provided, during which possible defects will be corrected. After successful testing - final payment. It is important that the contractor is ready for gradual expansion of functionality, as new tasks may arise during the work process. Priority - the shortest possible implementation time without loss of quality. It is preferable that the contractor is from Lutsk, but this is not a mandatory condition.Please indicate in your response to the application: Estimated implementation time; Cost; Technology stack; Examples of similar projects; Experience with Poster POS integration; Whether you are ready to work in phases; Whether you provide warranty support after launch.