Cannot upload keystore in code.appinventor

I have a big application that I moved from ai2 to code. I am trying to publish the bigger new version on Google Play but have an error message because I have two different keystores in the two accounts. I exported the Keystore from ai2 but cannot import it in code. Likewise, the option to delete the Keystore in code is not working (yet I can export the keystore).
How can I solve this?