German language school access issuance in TG club 1/3/6 months

The goal is to create a system "paid → access → reminders → disconnection → follow-up" without manual chaos.

1. Client's task:
The online German language school needed a process that:
• automatically grants access to a closed Telegram channel after payment
• records the tariff (1/3/6 months), payment date, and expiration date
• monitors the subscription period and does not leave people "forever" after expiration
• reminds about renewal before the tariff ends
• brings the student back through follow-ups if they did not renew on time
• provides the administrator with a clear picture: who is active, who is nearing the end, who is disconnected

2. Implemented solution:
I built a system: "Paid → became a student": after successful payment through WayForPay, the bot automatically records the payment in Google Sheets, assigns the access period, issues an invitation link to the closed channel only to the paying student, initiates a chain of renewal reminders, and disconnects access after the tariff ends (with subsequent follow-up).

3. How it works (step by step)
1. The student clicks "Choose tariff" in the bot
2. Chooses 1 / 3 / 6 months
3. Clicks "Pay" → goes to WayForPay
4. After successful payment, the bot shows confirmation
5. The bot records the payment in Google Sheets (row: tariff, payment date, expiration date, days remaining, student data)
6. The bot assigns the tariff to the student and calculates the expiration date
7. The bot issues an invitation link to the closed Telegram channel (logic "only for payers")
8. The bot monitors the term and sends renewal reminders: -3 days, -1 day, 0 day
9. If not renewed — the bot disconnects access (removes from the channel) and continues follow-up (for example, the day after disconnection)

4. What is automated:
• recording successful payment via WayForPay
• recording payments and statuses in Google Sheets (accounting instead of "chat in the head")
• granting access to the closed Telegram channel only to the payer
• calculating the term: expiration date + days until the end
• 3 touches before the tariff ends (-3 / -1 / 0 day)
• automatic disconnection after the tariff ends without renewal
• "follow-up" after disconnection to bring back for renewal

5. Stack:
• Platform: SendPulse Chatbot
• Channel: Telegram
• Integrations: Google Sheets, closed Telegram channel (optionally a Telegram group for managers)
• Payment systems: WayForPay + PayPal + semi-automatic payment system by details