Google Tag Manager (Firebase) error when registering an event

I have an integrated google and firebase tag manager in my iOS project. When I log the event it shows up in the firebase console but with google tag manager I keep getting this error

GoogleTagManager error: Error executing tag 1: Attempting to assign to undefined value 30,15,b,39,2,17,15,gtmUtils,common,isArray,7,15,a,7,8

      

        
        
        
      

    

This means that events are not shown in Google Analytics.

I removed all my tags, triggers and no matter how configured, this error always appears.

Has anyone seen this error before?