Tech Providers
Payment Aggregators/Gateways
Cloud Platforms
Collection Agencies

Believers Debt Consultants
https://www.believersdebt.com/Elision Technologies Pvt Ltd
https://www.elisiontec.com/Bizbloom Pvt Ltd
Dreams Debt Solutions Private Limited
Messaging Providers
Netcore

Meta whatsapp cloud
https://developers.facebook.com/docs/whatsapp/cloud-api/
ValueFirst
https://www.vfirst.com/