Microsoft team is not working on iphone

Hi - I have been using Microsoft Teams both on my laptop and iPhone for last few months. Couple of weeks ago suddenly it stopped working on iPhone though it is working fine on laptop. JFYI, I also have Skype for Business on my laptop and iphone and they are working fine. 

My organization uses Microsoft Authenticator and when I try and login to Teams on iphone, it takes me to my org page and asked for global password, which then does MFA thru Symantec's VIP access and after approving it, I get 'sign-in error'. 
I have uninstalled Teams and all other work applications (Outlook, Skype & Authenticator) and re-installed, restarted my iphone but the problem doesn't go away. My IT helpdesk tried several things and nothing worked and now they are asking me to do a factory reset of my iPhone, which I'm wary of doing.

Is there a way this issue can be addressed without factory reset? I'm really frustrated and is impacting my productivity from this productivity app!