Need a booking bot for personal virtual assistant services

I run a small personal/virtual assistant practice and I'm tired of juggling bookings through direct messages, phone calls and a messy spreadsheet. I need a booking bot that lets a client open a chat (Telegram or a website widget, open to suggestions on the platform), pick which task they need help with — document handling, making calls on their behalf, calendar and schedule planning, or a mix of these — and then choose whether they want a one-off session or a recurring subscription plan. After that the bot should show me as available in real time and let the client pick a date and time slot, confirm the booking and pay online before the slot is locked in.

The end client is usually a busy professional who wants this to feel effortless: three or four taps and it's done, no back-and-forth over chat. On my side I need a simple way to set my working hours, block out days off, adjust prices per task type, and see all upcoming bookings and payment statuses in one dashboard. Reminders before each session (for both me and the client) would save a lot of no-shows, and the subscription option needs to auto-renew and auto-charge unless the client cancels.

I don't need anything fancy in terms of design, but it has to be reliable and genuinely reduce my admin work, not add another tool I have to babysit. If you've built something similar before, I'd love to see examples.

Requirements:
— Task selector: documents, calls, planning/scheduling, or combined package
— Format choice: single session or recurring subscription
— Real-time calendar with date/time slot picking and availability blocking
— Online payment integration before slot confirmation, plus recurring billing for subscriptions
— Admin dashboard: working hours, pricing per task, bookings list, payment status
— Automated reminders for client and assistant before each session
— Cancellation and rescheduling flow with clear rules
— Mobile-friendly chat or widget interface, minimal steps to complete a booking