52111: GCM/FCM unknown errorERROR: 52111error-52111 page anchorNOTIFICATIONSERROR Error - 52111error---52111 page anchor GCM/FCM unknown errorgcmfcm-unknown-error page anchor Possible Causespossible-causes page anchor Unknown GCM/FCM error. Possible Solutionspossible-solutions page anchor If the problem persists, contact customer support(link takes you to an external page) and provide the time of the error and details about the requests that are failing.