We have found that the scam blocking settings on MetroPCS are problematic when forwarding calls to a MetroPCS device. There are two ways to overcome this issue:
1. Change your callerID setting to "Show called number" and this seems to fix the issue with call forwarding. Learn more here: Select incoming caller ID
2. Contact MetroPCS and ask them to disable all Scam Call Settings on your number and device. This has worked with mixed results. Let us know if this works for you.