Help getting old account back and old minecraft worlds

Hello, Joe. I'm Arturo, and I'll be glad to provide assistance with your inquiry today.

I’m sorry to hear you’re having trouble retrieving your Microsoft account.

Not only that, but as you don’t recall the email address, you may want to try recovering your account by submitting the account recovery form but using instead a previously linked phone number or previously created Skype username, which is not the same as our gamertag.

The form can be accessed here:
https://support.microsoft.com/accou...ery-form-b19c02d1-a782-dee6-93c3-dc8113b20c42

Besides that, I find it appropriate to mention that it is not possible to unlink a third party account from the Microsoft side of things. The process always needs to be done in the third party account linked accounts management site.

Furthermore, please refrain from sharing personal information, including email addresses, gamertags, etc.
As community users, we are not able to enter or check your account information, and everything we comment can be seen by anyone on the internet.

I hope you find this answer helpful to your inquiry. However, I'll remain attentive to any other one you may have.

Regards,

Arturo.

Minecraft saves are backed up on both the Cloud and on the console. Unfortunately if you the saved world has already been deleted from the old Xbox, there's no way of getting the worlds back. I suffered it when transferring my Xbox One Edition worlds to
Bedrock edition, unfortunately nothing can be done.

Try logging in to her account on Xbox one than Download Minecraft, There should be a option to load up old worlds from the data saved on that account.

Hello Aubrey__,

Thank you for posting in the Microsoft Community.

Yes. If you purchase Realms Plus, you can access all the packs, your personal server, and storage from any device with Minecraft Marketplace if you’re signed into your Minecraft: Bedrock Edition account.  

You can restore your old Minecraft worlds if you had them saved to your Xbox/Microsoft account. To do this, you need to make sure that you are signed in to the same Xbox/Microsoft account on your new tablet that you used to save your old Minecraft worlds. Once you are signed in, open Minecraft Bedrock and go to the "Play" tab. From there, select "Sync Old Worlds" and you should see a list of your previously saved worlds. Simply select the world you want to restore and it should download and be available to play on your new tablet.

Please see: Minecraft: Bedrock Edition Realms Creation FAQ | Minecraft Help

If you are having issues with this process please open a ticket here: Contact Us | Minecraft Help

If you deleted the old launcher, then I don't believe there's a way to get it back. Also to answer your question, that isn't a bug. When Minecraft accounts were Migrated to Microsoft, your Minecraft account was converted to the Microsoft account you merged it to. This means, you can't use the Minecraft account to sign in anymore and only the Microsoft account will work.

Hope this helps.