Zoom Call center not working since Salesforce summer release

We are on the Zoom App (AppExchange Link: https://appexchange.salesforce.com/appxListingDetail?listingId=a0N30000000qEuqEAE) not the Zoom for lightning app. 

We noticed that since the summer release, our production users can no longer click to dial in Salesforce. There is no error, but the phone icon is greyed out 

Does anyone have a solution for this?