Internet service and VoIP

I wanted to post an update. I was able to resolve the issue with T-Mobile by creating a VPN (virtual private network) server on my home fiber network in Minneapolis, I then obtained a router with VPN client and put it between my T-Mobile gateway and VOIP phone at the other location (Tucson). The VPN "pipe" tween the client and server passes VOIP traffic in an encapsulated manner, unaffected by whatever T-Mobile is doing. I could to do this only because I have two locations available, with two different ISP's (T-Mobile and US Internet), in other words, I leveraged my fiber network at my other home to hide the VOIP connection from T-Mobile. This solution cost me $32 (Amazon price for the GL.iNet GL-SFT1200 router).