continual sign in to iMessage

Hi sjzfse,

Thanks for reaching out to Apple Support Communities.

It sounds like you're having an issue with signing into iMessage with your iCloud account.

We're happy to assist.

We recommend checking out the steps in the section titled "If you are repeatedly prompted to enter your Apple ID password on your Mac or iOS device" from the article here: If you can't connect or sign in to iCloud

*If you have recently restored your iPhone, iPad or iPod touch from an iCloud backup, the restore may not have completed. Stay connected to a reliable Wi-Fi network and power source until the restore finishes. Follow these steps if iCloud Backup couldn't be completed or you can't restore. 

*If you recently changed your Apple ID password, you might need to update your sign-in informationwith iCloud services you use. Make sure that each service is using your updated sign-in information on your device.

*Check if you have Automatic Downloads enabled. If there is content ready to be downloaded, you may be prompted to enter your Apple ID and password to continue. Learn how to resume interrupted downloads. 

*If you are an organizer, parent, or guardian of a Family Sharing group, check if the prompt is a request from a child family member to make an iTunes Store purchase. You can then approve or decline the request. 

The reason why we’re recommending the steps above because they directly address the issue you initially posted about: you are repeatedly prompted to enter your Apple ID password.

Should the issue continue, follow-up with the steps in this article: If you can't sign in to your iMessage account or FaceTime on your Mac

Please do not hesitate to reach back out to us if you have questions or need any additional support.  

Cheers!