Trouble removing grayed out mail boxes from the favorites bar in mail for Mac

Hello,

I need help with removing a couple of mail boxes from my favorites list in Mac Mail . They are grayed out and I've tried to delete or remove them, but with no success.
I called Apple Accessibility and they could not remove them or delete them.
I did notice this occurred when I had to sign in into my Exchange account the other day. The exchange account looks exactly like my hotmail account that I first used to sign into my mail app in Mac. I even tried removing the exchange hotmail account and the two mail boxes are still on my favorites list.
The thing is The other hotmail account I used to sign into mail is active, but the Exchange isn't.

I appreciate the help . Hopefully, I explained the issue clearly.

Thanks