Hi all, 
I have a custom object "Custom1" on which we added an Approval process. The process is easy when the object is approved by the approver then I have a Final Approval Actions that is set to update a field in "Custom1" Called is_approved ( True/False - Checkbox)

Then using a Flow builder I set that if the field is is_approved: True then it should trigger the flow that will update a field in many records linked to "Custom1"

For some reason, the Flow Builder is not triggered when it happens after the approval process. However, if I edit the field is_approved to TRUE manually then the flow is triggered 

Could you please help me to trigger it after the approval process?

FYI: