I don’t know my @icloud.com address [duplicate]

This question already has an answer here:

  • How can I bypass Activation Lock? 4 answers

Someone stole my iPad and I got it back. Now the device is requesting for activation using @icloud.com address which I can’t remember setting up.

Though I still have my Apple ID login details but can’t use it to log in. I tried using my Apple ID, but it didn’t work, I logged into iCloud, but could not see the @icloud.com address. I requested Apple for my data, but still couldn’t find the @icloud.com address.

How do I resolve this issue?