sign up is stuck half-way, confirmation emails are not coming

I tried to go through sign up process, but email confirmation message never arrived to me. I requested in many time but it didn’t help (all other mails come to me just fine, it’s google mail). Then I tried to login to GitLab via GitHub account with the same email and got " Sign-in using github auth failed. Sign-in failed because Email has already been taken."

Can I do something about this? GitLab doesn’t seem to provide any support :confused: