Google calendar accepted invites not synching
When I accept an Google Calendar invite on my Apple iPhone 7 it goes into the default calendar on my phone but doesn't then sync with my calendar on my iMac. All devices are running latest OS/iOS. All other appointments entered manually are synching perfectly. Not sure whether invites accepted on my iMac are synching with my iPhone as haven't accepted one on the iMac yet. Any ideas what is happening?
iPhone 7, iOS 11.2.6