Please compare installation steps you used with THESE by mobilefish dot com to configure ChirpStack under Ubuntu.
I did what he recommended verbatim (except I’m on US915 and some of my sensors require the ChirpStack network server to have 500kHz channels enabled - section 5.2.3 HERE ) and it worked the first time! He has a LOT of very informative LoRaWAN-related material that you simply MUST at least skim and be aware of. He’s saved me a lot of hassle!