Autofill on iOS always resulting in "no items in your vault"

Using a self-hosted instance of bitwarden (vaultwarden docker on unraid).
iPhone 15 with Bitwarden app, set as the only autofill source for passwords in the iOS settings.
Whenever I try to login, tapping ‘passwords’, Bitwarden app opens, but resulting in “There are no items in your vault for this website/app.”
When I manually search for the website/app name, it finds the entry.

Trying out Bitwarden to maybe move away from Keypass. However, this manual search is keeping me from deciding for Bitwarden.
Have tried different settings for session time-out, same result every time.

What is causing this behaviour, and how to solve this?
Thanks in advance.

@moonbelly Welcome to the forum!

Vaultwarden is not supported by Bitwarden, as it is an independent product. From time to time, there will be compatibility issues between the official Bitwarden client apps and the Vaultwarden server, when Bitwarden implements changes to its own server software (which have not yet been mimicked by the Vaultwarden devs).

It is generally not possible for members of the Bitwarden community (users or developers) to help with such issues, but Vaultwarden has its own community spaces where you can seek support:

 

Vaultwarden developers have clarified their position on providing support for Bitwarden client incompatibility issues in the notice at the top of the Vaultwarden project’s GitHub README: