iMessage and iCloud accounts do not match

Hi iMessageicloundnotmatch,

Thanks for posting in Apple Support Communities. Since the error message mentions the iMessage and iCloud accounts don't match on your iPad, make sure that you see the same Apple ID from Settings > [Your name] as the one that appears from Settings > Messages. The following is from Set up Messages on iPhone - Apple Support.

"Sign in to iMessage

When you sign in to iMessage on your iPhone, your messages are kept up to date, backed up, and available on all your Apple devices where you’re signed in with the same Apple ID. When you communicate with others using iMessage, you can use more apps and features, like read receipts, undo send, message editing, audio messages, collaboration, replies, and more.

1. Go to Settings  > Messages, then turn on iMessage.
2. To select the phone numbers and email addresses you want to use with iMessage, go to Settings > Messages > Send & Receive, then choose from the available options below “You can receive iMessages to and reply from.”

Since you also mentioned using Mac, check to make sure the correct information appears from Settings > Messages > iMessage there as well. Reference Set up Messages on Mac - Apple Support if needed.

Kind regards.

Hello iMessageicloundnotmatch,

At this point, you’ll need to contact Apple Support directly to look into this issue further with you: Get Support

Take care.

Hello iMessageicloundnotmatch,

As previously recommended, you'll need to continue working with Apple Support on a solution to this issue.

We'd recommend revisiting your case and to give them a call to discuss this further: Contact - Official Apple Support They would need to take it from here.

Cheers.