Help with two-factor authentication

Hi.

A couple of weeks ago, my phone has been stolen. I have my authentication app on it, but since I don't have it, I have problems to log in a certain account. I didn't have a backup, so because of that, I'm unable to gain access to my account. I contacted with their support center, but they give me an unsatisfying answer, telling me, I'm unable to restore my access. I would like to ask some help. Is there any way, to get back those informations to help me restore my access?

Thank you.