my old hostname is still active????

I have no idea what's going on. my server once run fedora, and its hostname was fedoraserver. I recently installed AlmaLinux, and now its hostname is tserver. today I was looking at the logs of jellyfin and... Slow HTTP Response from http://fedoraserver:8096
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...
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* realization *
...
WTF!!!!! It's like I saw a ghost. do any of you know what's going on?

even more strange:

$ host fedoraserver                                                                                                                                                                                    
fedoraserver.station has address 192.168.1.4
fedoraserver.station has address 192.168.1.13
fedoraserver.station has address 192.168.1.41
fedoraserver.station has address 192.168.1.10
$ host tserver                                                                                                                                                                                         
tserver.station has address 192.168.1.13
$ host 192.168.1.13                                                                                                                                                                                    
13.1.168.192.in-addr.arpa domain name pointer fedoraserver.station.

I'm... I'm scared