Unable to update merchant details once the merchant is linked with Facebook ad account

steps:
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1. Create a merchant with Facebook enabled and save it.
2. Do the page linking process for the merchant.
3. Login to TP site and link the ad account to the merchant.
4. Now, come back to the Reseller UI and switch between the merchants.
5. Verify the Facebook page linking status for the merchant created in step-1.
6. Also verify the facebookAdAccount value in the json column in tp.customers table. (Expected: facebookAdAccount value should be available)
7. Now, update any of the mandatory field for the merchant created in step-1.
8. Save the merchant details.

Expected: Merchant details with the updated values should save fine.

Actual: Merchant failed to save the updated details.

Note: This is happening because TP is not allowing any updates to the customer after an ad account is linked to the merchant. Tried to update the merchant after disconnecting the ad account in TP, merchant details saved successfully. Also verified in TP, ad account linked again to the merchant automatically.

See the attached Error log.