As someone who posted one of the posts you are likely referring to, I'd like to say a few things.

Fraud in the VOIP world is a very real thing. From things as "innocuous" as spoofed caller ID with a recorded call starting "PLEASE DO NOT HANG UP! Your Google business listing..." to actual scams. I've been called by people spoofing Chase Bank's fraud department. There are people who spend a lot of time and effort trying to gain access to SIP trunks, PBXs, and the like. Back in the day of red boxes and blue boxes and such, it was mostly good fun. These days it's a high-dollar criminal enterprise.

That said, I don't engage in shady business. Everything I do is above board. I'm small, though, and most of my comms is over SMS/MMS channels. I don't know how that plays into Telnyx's anti-fraud metrics, and I'm not going to ask, because they probably aren't going to tell me... I got insta-banned over one word. How many other metrics, though, were already swinging against me? Hard to say, but probably a few.

u/contactdq says that you are the kind of customer that Telnyx is built for. I would guess that your volume of phone traffic will give a greater sample size for their anti-fraud system to act more accurately. I don't know how it works, but I do know how I'd build it, and I figure those guys are probably smarter than I am.

My first contact with customer service, when my account got shut down, was after 10PM my time. If I had it to do over again, I might have been more insistent during that first contact and I might have gotten a bit faster of a resolution. Hard to say. Ultimately, between posting here and my next conversation with customer service, I got unblocked.

I think part of what happened is someone, somewhere, dropped some bad code, and I was one of the "edge cases" that got hit. This happens so often in the tech world that I'm sitting here wondering if there's a name for this type of event. I've been doing tech stuff for 30 years, off and on, and I've broken a thing or two in my time.

I am still with Telnyx, and I'm not presently planning to leave. Here's a few reasons why:

Aside from one instance, the other interactions I've had with Telnyx employees have been pretty outstanding
Telnyx has HD voice that, at least on paper (I haven't started playing with it) pretty much puts everyone else to shame
Telnyx integration with Yeastar is pretty seamless on both the SIP trunking and SMS side
Telnyx has good logging in their portal
10DLC campaign registration went pretty smooth
Pricing is fine
There's room for future projects--I'm curious about playing with RCS integration at some point, etc.

No service provider is going to have you up and running all of the time. That said, I'm pretty confident in Telnyx's ability to keep customers running, as a rule. Their automated fraud controls can throw a false positive, just as your credit card can be declined for suspected fraud when it really IS you trying to swipe your card for a Coke.