Your case and question don't portray sincerity and it's incomplete at the same time. Is the wallet custodial or noncustodial? Do you still have crypto assets in it?
Based on these, if you don't have crypto assets in it, why waste your time, go for another wallet for privacy and security reasons. But if you have crypto assets in it and it's custodial, contact your wallet company with your original details for a reclaim. However, if it's noncustodial, signing a known message with your private key will be the most viable way out.
#Update:Huh.. But we can both signing from my wallet...
*It's not a real situation! It's just a model!
Lol...In this case, it's your carelessness and the person has all the needed information of the wallet. Quit it and move all your coins if you have any, and if still possible.