Howdy User1768,
It sounds like you're being prompted to enter in the password to a different Apple ID when you go to update WhatsApp. In this scenario, if you want the application to be associated with your Apple ID, you'll need to remove it and download it again using your credentials. As a heads up, we recommend reaching out to that developer to learn what happens to your data when you perform this action.
To contact an app developer, check out the steps here: How to contact an app developer
Outside of that, the only way to continue getting updates of that app would be to provide the credentials for the Apple ID account being displayed.
We hope that helps.
Take care.