TGBot appointment with a specialist with the ability to change available dates

Implemented on Sendpulse + Google Sheets.
Goal:
1. Provide users with the opportunity to sign up for a consultation with a psychotherapist by selecting the desired date and time from a menu in the form of buttons.
2. Allow the administrator to change the available session dates to one day ahead via the /admin command using a button.

How it works:
Users choose individual (with date and time selection) or family therapy. (through private messages) -- Screenshot 1 and 2 --
After selecting the date and time, the person goes through a cycle of collecting basic information. -- Screenshot 3 --
The administrator receives a message that a specific date has been booked by the person (with their details). The message also contains a section about the need to change the booked date. -- Screenshot 4 --

Through the /admin panel, which is accessible only to the administrator via a tag, they can read a brief instruction on how the date change works. -- Screenshot 5 and 6 --

- Screenshot 7 - demonstration of how the changed date appears to other users.
All applications are also sent to a Google Sheet.

Implemented using global variables, which provide, albeit a small, but an opportunity to edit information directly through the bot.

Thank you if you read to the end :)