Downgrade Google Identity Platform back to Firebase Authentication

[SujeetLahare]

We used Firebase Authentication and were happy about it. Then I clicked the "migrate to Identity Platform" button — but that was a mistake. We don't use any of the advantages but end up paying the fees.

How can I downgrade it back to Firebase Authentication? I found that we can disable Identity Toolkit API — but won't it remove all the user records (which is definitely not an option)?

my project id- satnami-samaj

my project number - 586234319051

Thanks.