Sharepoint user invite problem

Hi,

We have a sharepoint website with which we share files with an external company.

The external company has setup their employes with two registered email address's with Microsoft.

JoeBloggs@

JBlogg6@

From past experience I need to invite the 2nd email address JBlogg6.

When I invite JBlogg6 sharepoint already seems to know the first email address and autocorrects it to JoeBloggs.

No matter what I try, it always autocorrects the invite.

I have tried wiping the all internet data from Edge, clearing the email address from Site Collection in Sharepoint, nothing seems to help.

I used to be able to invite both email address's individually, which worked fine.

Is it possible to stop Sharepoint from autocorrecting my email invite entries?

Any help appreciated.