Unable to connect to a Linux port from Windows

I'm trying to run a gRPC service on Linux while running a client on Windows.

I seem to be unable to test the Linux port that I use from my Windows machine. Both machines are in the same network. Windows 10 and CentOS 8.

Here's what Powershell gives me:

PS C:\WINDOWS\system32> tnc server_ip -p 55555 -Debug
DEBUG: TCP connect to (server_ip  : 55555) threw exception: Exception 
calling "GetResult" with "0" argument(s): "No connection
could be made because the target machine actively refused it 
server_ip :55555"

Confirm
Continue with this operation?
[Y] Yes  [A] Yes to All  [H] Halt Command  [S] Suspend  [?] Help (default is 
"Y"): y
WARNING: TCP connect to (server_ip  : 55555) failed


ComputerName           : server_ip 
RemoteAddress          : server_ip 
RemotePort             : 55555
InterfaceAlias         : Ethernet
SourceAddress          : client_ip
PingSucceeded          : True
PingReplyDetails (RTT) : 0 ms
TcpTestSucceeded       : False

I don't know much about Linux, but here are some commands that I tried to check that the port is open and the service that uses it is running, and the results that I got:

[user@localhost ~]$ grep -w 55555 /etc/services
test        55555/tcp       # TestService

[user@localhost ~]$ sudo lsof -i -P -n | grep LISTEN
[sudo] password for user: 
GrpcServi 10933         user  166u  IPv4 1090871      0t0  TCP 127.0.0.1:55555 (LISTEN)
GrpcServi 10933         user  167u  IPv6 1090874      0t0  TCP [::1]:55555 (LISTEN)

[user@localhost ~]$ sudo netstat -tulpn | grep LISTEN     
tcp        0      0 127.0.0.1:55555         0.0.0.0:*               LISTEN      10933/./GrpcService 
tcp6       0      0 ::1:55555               :::*                    LISTEN      10933/./GrpcService 

[user@localhost ~]$ sudo netstat -tulpn | grep :55555
tcp        0      0 127.0.0.1:55555         0.0.0.0:*               LISTEN      10933/./GrpcService 
tcp6       0      0 ::1:55555               :::*                    LISTEN      10933/./GrpcService 

[user@localhost ~]$ sudo ss -tulpn | grep LISTEN                                               
tcp   LISTEN   0        128              127.0.0.1:55555          0.0.0.0:*      users: 
(("GrpcService",pid=10933,fd=166))                                                                                   
tcp   LISTEN   0        128                  [::1]:55555             [::]:*      users: 
(("GrpcService",pid=10933,fd=167))                                       

[user@localhost ~]$ sudo ss -tulpn | grep ':55555'
tcp   LISTEN   0        128              127.0.0.1:55555          0.0.0.0:*      users: 
(("GrpcService",pid=10933,fd=166))                                       
tcp   LISTEN   0        128                  [::1]:55555             [::]:*      users: 
(("GrpcService",pid=10933,fd=167))                                       

[user@localhost ~]$ sudo lsof -i -P -n | grep LISTEN
GrpcServi 10933         user  166u  IPv4 1090871      0t0  TCP 127.0.0.1:55555 (LISTEN)
GrpcServi 10933         user  167u  IPv6 1090874      0t0  TCP [::1]:55555 (LISTEN)

[user@localhost ~]$ sudo firewall-cmd --zone=public --list-all
[sudo] password for user: 
public (active)
  target: default
  icmp-block-inversion: no
  interfaces: enp2s0
  sources: 
  services: cockpit dhcpv6-client ssh
  ports: 3389/tcp 3389/udp 55555/tcp 
  protocols: 
  masquerade: yes
  forward-ports: 
  source-ports: 
  icmp-blocks: 
  rich rules: 

I also tried disabling firewalls on both Windows and Linux to check if that might help, but to no avail.