[100% WORKING SOLUTION FOR HEARTBEAT API]
I have written a step by step post on how to solve it i.e. disabling the Heartbeat API eaither completely or fraction of it or if you don't want to disable it then how to control it.
Check it out at Solution to Heartbeat API
You can also message me or comment below the post if you have any query, i'll be glad to assist.
[I HAVE TESTED ALL THIS FEATURES AND FOUND IT WORKING]