Power Platform Community Forum Thread Details

I have SP list A and SP list B which has one to many relationship (parent - child relation) , I looking to create approval flows by giving permissions using http request .
Now the scenario here is I might be using Standalone Canvas App or SP customize form, user create a request then it goes for approval to Department Head(DH) , now the DH gets contribute permission and user gets read permission.

If the DH approvals the request then it goes to COCM group for approval and now here DH & User gets Read permission.

But if the DH or COCM group rejects , then the user can edit the record for which the user gets contribute access.

Now the permission we have to set to both the SP List.

How shall I create the flow or steps to achieve this ?