Play store key firm not valid 2024

[silver2024]

Hi, i'm trying to publicate an app on Google Play Store.
I got this error message:

"You've uploaded an APK or Android App Bundle that's signed with a key that's also used to sign APKs provided to users. You're participating in the Play App Signing program, so you should sign your APK or Android App Bundle with a new key before uploading it."

Is there a step by step tutorial to fix it?
I found other posts about it, but can't find a solution.

Example:

Use a valid app signing key to continue

I have a new app I want to publish on Google play. Since it is new I understand that I have to sign it, and use the .AAB file. Searching through the internet it is not so easy to find out how to do this. But this is what I have done so far: I build the .apk file for the app. According to @Anke a new keystore is created. I download it: [image] And I store it in a folder called app-signing. I go to the play console, and select export and upload a key from a java keystore: [image] I th…

How you
" 1. Export and backup the current keystore.
2. Delete the current keystore in the Designer (AI2)."?

Thank you