Some subdomains do not work

I am trying to set cloudflare tunnels via cloudflared to some docker containers. I am trying out different subdomains, however it isn’t working as intended.

The following do work:
oo.example.com
onlyoffice.example.com

The following don’t work:
tnas.example.com
tnas001.example.com
oo-001.example.com
ootnas.example.com
ooonlyoffice.example.com

Why do some work and others don’t? I don’t understand.

Each running on a different port? :thinking:

All of these subdomains are linked to the same container. Nothing in the settings or anywhere gets changed other than the subdomain itself.