Version code 1 has already been used. Try another version code

You have two ways to solve this, if you released your bundle already, then you have to update your version code like in balu k’s answer,

If you’re still developing and pushed app bundle for say, testing, and then you delete it, this bundle is saved as a draft with that version code. Therefore, it says that you can’t use the same version because it already sees another one with the same version name.

Here’s how you fix it:

1. Go to the release section
2. go to app bundle explorer, in the top right you should see a dropdown button for you app version, click on it.
3. A bottomsheet will show containing all the previous app bundles you uploaded it. Delete the one with clashing bundle version and you’re good to go.

Hope that solves your problem.