OS: Linux Mint, regularly updated, incl. Linux Kernel

PROBLEM
A. no ssh connection to my local computer possible, even not ssh [myname]:127.0.0.1
B. ssh localhost, on the other hand, works
C. entering sshd: ALL and ssh: ALL in /etc/hosts.allow does not help

Your help would be appreciated!

DETAILS

1. sudo ss -tulpn | grep :22 yields
   tcp LISTEN 0 128 0.0.0.0:22 0.0.0.0:* users:((“sshd”,pid=1075,fd=4))
   tcp LISTEN 0 128 [::]:22 [::]:* users:((“sshd”,pid=1075,fd=3))

2. ssh -X -vvv [myname]@[my-ip-address] [login attempt from somewhere outside]
   OpenSSH_8.9p1 Ubuntu-3ubuntu0.7, OpenSSL 3.0.2 15 Mar 2022
   debug1: Reading configuration data /users/[myname]/.ssh/config
   debug1: Reading configuration data /etc/ssh/ssh_config
   debug1: /etc/ssh/ssh_config line 3: Applying options for *
   debug2: resolve_canonicalize: hostname [my_ip_address] is address
   debug1: hostname canonicalisation enabled, will re-parse configuration
   debug1: re-parsing configuration
   debug1: Reading configuration data /users/[myname]/.ssh/config
   debug1: Reading configuration data /etc/ssh/ssh_config
   debug1: /etc/ssh/ssh_config line 3: Applying options for *
   debug3: expanded UserKnownHostsFile ‘~/.ssh/known_hosts’ -> ‘/users/[myname]/.ssh/known_hosts’
   debug3: expanded UserKnownHostsFile ‘~/.ssh/known_hosts2’ -> ‘/users/[myname]/.ssh/known_hosts2’
   debug3: ssh_connect_direct: entering
   debug1: Connecting to [my-ip-address] [[my-ip-address]] port 22.
   debug3: set_sock_tos: set socket 4 IP_TOS 0x10
   debug1: connect to address [my-ip-address] port 22: Connection timed out

3.netstat -tnlp
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN –
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN –
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN –
tcp6 0 0 :::22 :::* LISTEN –
tcp6 0 0 ::1:631 :::* LISTEN –

4.ps -ef | grep sshd
root 1075 1 0 12:48 ? 00:00:00 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
[myname] 21645 16166 0 14:50 pts/4 00:00:00 grep –color=auto sshd

5. The DSL provider claims not to block requests to port 22

6. On my computer sshd (root) and ssh-clien ([myname]) are running

7.I do not use a firewall

8. telnet [my-ip-address] 22
   is taciturn and quits after some time

9. ping works