Hello,

The Related posts were coming from the Jetpack plugin.

I have disabled the option from Jetpack → Settings → Traffic. And the issue was fixed.

Screenshot for Clarification: https://gyazo.com/d7e9325f646a18012c231d8a6a0ef69c

Let us know if there’s anything else we can do for you! You can always reach us at any time. We are always here to help you.

Have a wonderful day.

Topic Closed.
Best Regards.