in-app purchase

In the same app on your iPad, open the app, find the place in the app where you paid for the ad free version and see if there is a Restore purchases option.

If there is, tap it to restore your in-app purchase to the iPad.

Best of Luck to You!

What exactly did you buy on your iPhone? Was it an App for add blocking? Or did you pay for an add free version of an app? If you did, you should reach out to the app developer to see if what you paid for on your iPhone should also mirror the app on your iPad. It may not.

Then you should contact the app developer for that app and inquire about your iPad's version.