Urgent: WhatsApp API Developer for Crypto E-Commerce Bot (WATI/Make.com)

I'm launching a high-volume WhatsApp store (5k+ users/day) and need an expert to:

Fix payment flows:
- Crypto via NOWPayments
- Gift card uploads
- Address payment gateway integration errors

Optimize WATI/Cloud API for low-latency messaging:
- Message delivery speed
- Message synchronization
- Error handling and retries

Debug Make.com/Zapier automations and manage Airtable/Firebase integrations

Requirements:
- 3+ WhatsApp Business API projects (WATI preferred)
- Experience with payment gateways (crypto or Stripe/PayPal)
- Airtable/Firebase automation skills
- Ability to work under a 4-day deadline