Retrieve issue in Repositoy

I have imported issues file from one repository (emgsstars / edumsia.gov.my ) to another (emgsstars / stars ) after i clicked the button import which will import the file to (emgsstars / stars ) i noticed that all the other 280 issues and more that were existing in the repo are no longer there. i just performed this 30 minutes ago and it will be a disaster if we lose those issues. please help urgently. please help to restore back to most updated copy before i did the overwrite it.

HI, If you could please open a support case at support.atlassian.com, one of our engineers can review your case. Cheers,

Gary