Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Error 44 indicates the Office apps cannot find your Office licence.
Use the process on this link to remove the Office licence, then try logging into the Office apps again to test if your licence is correctly recognized.
If that does not resolve the problem, log into your Microsoft account on this link, is your Office licence listed correctly there, or if that is a subscription, check the expiry date listed on your subscription, is that listed correctly.