SPO List Content Approval not working when changing attachment using Power Apps Form

Folks, 

We are using SPO list with Content Approval enabled. It is functioning perfectly in all conditions when using Default SharePoint Form. But when using Power Apps Form, 'Approval Status' has no impact when we remove or re-upload attachments (if the status was approved, it remains approved) - again, any other changes to any fields will change the status to 'Pending'. 

Is this a default behavior? or is this something we can fix in the attachment control in Power Apps or is there any addition to be performed in Lists Settings?

Appreciate your valuable advises. 

Thank you all in advance. 

-SHB