Why don't google firebase sms always arrive?

Question

firebase

Good day to all.

Made verification by SMS through google firebase. Until recently, it worked well, but over the past month, the number of SMS "stuck" somewhere has become more frequent. Google returns a successful response, phones are not banned, etc., sometimes SMS arrives to the number and quickly enough, sometimes it does not arrive at all. Chance somewhere around 30 (success) 70 (fail).

Are there any ideas what could be the reason where to dig?

Answer 1

cheap sms gateways
use twillio, they are more expensive, but also not without sin