can't change email adress on profile

For some reason the site won't let me change my email adress.
It says it is already in use by another user, but I only have one account.
The email adress I have listed on this site went offline 🙁

Are you sure (really, really sure) you typed the correct address?

There is a small glitch when you have been invited to the site then sign up with a different email address.

The old invited account sits there invisibly, and in your case, is preventing you from changing your address.

Send feedback with the new email address you want and this can be resolved.

-Russ

Yes, I am positive I typed the right adress (I tried it 5 different times, and I've had the adress for maybe ten years). Thank you for your your help. I will try what you suggested.