Hello REng84
Welcome to the Microsoft community!
I have realized that you encountered while using the transcribe feature in Word for the web with uploaded audio files. We completely understand your frustration, especially when the transcription feature is the main reason you subscribe to Office 365. We appreciate that you've already tried troubleshooting steps like signing out/in and using a different browser.
The error message you're seeing, while suggesting to try again later, often relates to a few factors if it persists:
1. Monthly time limit for uploaded audio transcription: If the total duration of audio you've uploaded and requested transcription for this month exceeds this limit, the feature will be temporarily unavailable until your allowance refreshes next month. This could be one reason why you're persistently seeing this message.
please refer to:Transcribe your recordings - Microsoft Support

2. Required "Connected Experiences" setting: For features like transcription that rely on cloud services to function correctly, it's necessary to ensure specific "Connected Experiences" are enabled in your Office account.
please refer to:Connected experiences in Microsoft 365 - Microsoft Support

Since you're primarily experiencing the issue in Word for the web, we suggest trying the same operation in the desktop Word application that's part of your Office 365 subscription (if you have it installed). Sometimes, there can be subtle differences in how the desktop and web apps handle certain tasks, and this can help determine if the issue is platform-specific or related to your account/file itself.
After receiving your feedback, we also performed a quick test, and the Word transcription feature itself is currently functioning correctly on our end. Considering the error message mentioning "right now" and suggesting to "wait a few minutes," combined with the possible reasons mentioned earlier (especially the 300-minute limit), our initial assessment is that this is likely a temporary state. If you have indeed reached the usage limit, the feature should automatically become available again in the next billing cycle/month. If it's not the time limit, and your "Connected Experiences" settings are correct, then it might indeed be a temporary service fluctuation.
We recommend checking your transcription usage for this month and verifying your privacy settings. If you confirm you haven't exceeded the limit and the settings are correct, and the issue persists even after trying the desktop version of Word, please try again after waiting a bit longer.
We hope this information helps you pinpoint the issue. Thank you for your patience and understanding.
Sincerely,
Coco - MSFT | Microsoft Community Support Specialist