Hey, I totally get the frustration trying to get a SIP trunk working with inbound calls can be a real headache, especially when the provider insists everything is open I had run into similar credential errors before, and it often comes down to something subtle in the registration or headers rather than the network itself There might be a small config detail that’s throwing things off If you want, I can take a closer look at what you’ve tried so far and see what’s going on @Jesh