Unable to associate due to failure in acquiring purchase from the app store. Please try again.
In most cases, this issue occurs when Microsoft Office is not able to find a purchase associated with your Apple ID.
To resolve the issue:
Check your Apple subscriptions page to verify whether your Microsoft 365 subscription is active.
If your Microsoft 365 subscription is active, try the steps in this article: Restore previous purchase for Office for Mac.
If your Microsoft 365 subscription has expired, renew your subscription.
If the problem persists or if you think you should not be seeing this error, please contact Microsoft Support.