cannot join a meeting

My company has a corporate account.  About two weeks ago, the credentials to join a meeting failed to work. After several attempts by the host to give me access, I tried via my cellphone.  All of the messages opened my zoom account on my cellphone.

I do not want to use my personal cellphone. for zoom meetings outside of an emergency.   As part of my job, I need the flexibility to interview stakeholders  (informants) who are not a part of the company via zoom. 

The product is failing and I would like a remedy as quickly as possible.