If you got email from PayPal with subject line “PayPal Instant Payment Notification Warning” and the body says something similar to the text below, you can fix it from your PayPal account area.
Please check your server that handles PayPal Instant Payment Notifications (IPN). Instant Payment Notifications sent to the following URL(s) are failing:
If you do not recognize this URL, you may be using a service provider that is using IPN on your behalf. Please contact your service provider with the above information. If this problem continues, IPNs may be disabled for your account.
Thank you for your prompt attention to this issue.
Step 1: Go to profiles
Step 2: Go to selling preferences
Step 3: Go to “Instant payment notification preferences” under “Getting paid and managing my risk” and hit update
Step 4: Edit the setting (Change URL of IPN setting) or Turn off to disable IPN.
It will fix your PayPal Instant Payment Notification Warning