SyncUp KIDS watch still not working on T-Life app

Ever since SyncUP KIDS app switched to T-life app, I cannot add my husband as a guardian, hence, he cannot track our kid. We went to 2 different T-Mobile retails, none of them could help us.  We got a ticket number. 

I can at least see my kid's location but I cannot see my husband's location either.  

It has been 3 weeks, none of the tech support team members contacted us back.  While waiting we did everything - uninstall, install, repeatedly. Nothing has worked so far.  I sent invite links to my husband, and the links do not work.  When he tries to pair the watch manually, it keeps saying "Something went wrong. Please try again".  We are extremely disappointed with T-Mobile removing SyncUp KIDS app before it tested and integrated successfully.

If anyone found a solution, please let me know!