(Ubuntu 19.04) Getting "error connecting to yubikey!" when attempting to open Database

[pjbuterbaugh]

Able to access this database on a W10 build 1909 + Android 8 device, but can't open it on my install. Currently using mono to run.

Have yet to test if there's any difference in the end result by using Wine.

To be clear: not seeing any sort of acknowledgement or response from my Yubikey. I can use it in Firefox to authenticate using FIDO/U2F but otherwise I cannot use it in Keepass2.

[alexander-thiesen]

Have you tried this?
https://support.yubico.com/hc/en-us/articles/360013708900
I found it here: https://support.yubico.com/hc/en-us/articles/360016648939-Troubleshooting-Failed-connecting-to-the-YubiKey-Make-sure-the-application-has-the-required-permissions-in-YubiKey-Manager

[eduardable]

This might happen if you set it up to use slot 1. Upon restart, it resets to slot 2. Simply select slot 1 again (Tools->KeeChallenge Settings) and it should work.