Inseego MiFi m2000 not working with 8x8 Work - No Sound

I'm on the road a lot, and as a T-Mobile customer I naturally looked to T-Mobile for a wireless solution when I needed a hotspot.  I was sold on the Inseego Mifi M2000 because of its 5G connectivity.  The problem is, one of the apps I regularly use is 8x8 Work, which is the app that enables me to use my phone, tablet and laptop as a virtual extension of my office phone to send and receive calls, and it doesn't work when I'm connected to the 8x8 network via the M2000.  While I can dial and recieve calls, there seems to be some port blocking going on by T-Mobile that prevents any sound from being received or heard when using the 8x8 app.  I first reached out to 8x8 to see if they had any work around, but unfortunately the issue seems to be something on T-Mobile/Inseego's end, and they have offered no solution.  There are no obivous settings that I can change on the hotspot to fix the issue either. It's such a big problem that I'm thinking of leaving T-Mobile after being a customer for many years as I need this app to work and T-mobile has no resolution.  I'm hoping someone else has come across this, or a similar, issue, and can give me some guidance. Thanks to anyone who can help.