Hey All
I deactivated my Shopify account and need to remove the shopify channel.website from my Facebook and Instagram. I have tried to do this via FB but unsuccessful as it still shows. I am unable to log back into my account to check if any channels are still active and linked to my business manager ID. please help 
Suppose you have already tried to remove your Shopify sale channel from your Facebook but were unsuccessful. In that case, I suggest that you log back to your Shopify account to check and remove your Facebook and Instagram from Shopify.
If you want to log back in, you will have to enter your credit card details and reactivate your store for a while.
Shopify may issue you a bill. But you can contact Shopify Support to discuss the refund.
If you feel like my answer is helpful, please mark it as a SOLUTION. Let me know if you have any questions!