Admin page error "TemplError"

Everything used to work fine.
But I cannot access the admin page no more now and I can figure out why and how to get it back.

It gives me the error “TemplError” when I try to access it.
I recently switch my docker image to /server:webauthn after already switching to the new vaultwarden image.
I remember that the migration messages goes for ever and had to kill it ctrl+c and restart the docker in daemon mode.

I have another instance working fine and I compared both settings and I can’t see much of differences in between but this instance got the admin page showing fine.

How can I do ?
What can I try to solve this issue ?

Thanks for your help if anyone has some solutions to propose or run into similar isssue in the past.