Updated: Wednesday, 7 April
iPhone is your big asset and you use iMessage app on your iPhone. But if your iMessage is not working and it is showing activity error on iMessage then it is a big problem on the iPhone. This is a problem which you need to fix especially with new iOS updates like iOS 12. Now the question is how to fix the problem. Here is how you can fix the iMessage activity error on the iPhone.
You can use this method to fix activity error on iMessage. This solution has been found to be one of the most successful methods to get iMessage working again.
There are other methods to fix the problem as well. But you can try this method as it works well to fix the problem. Now you can enjoy iMessage or Facetime on your iPhone and if an activity error is where you can try the above steps to fix the problem.