I have a RPi 3 Model B+ and I used it as WiFi bridge for a device which has only ethernet port. After the initial setup it worked and then after one reboot the SSH stopped working.
It’s connected to WiFi, I can see it online on my router. I can ping it from my PC. I can access folder which I shared over the local network from it. The only thing I can’t do is remote into it with RDP or SSH with Putty.
SSH should be running:

I have a raspberry pi, with rpi os lite.
I ssh into it and have been using it for some time.

I was able to connect to Raspberry Pi via ssh. In fact I used headless installing of diet pi on my Raspberry Pi and then I was able to connect to my Raspberry Pi via ssh, however today I am no longer able to connect to my Raspberry Pi.
First I figured out that the ip address can be static or dynamic, and it may change, so I thought to find the IP address of my Raspberry Pi and connect to it via ssh.
I googled and tried different solutions.
1st attempts : I used arp-a command in cmd and find out a list that shows me ip address and the physical address, but I didn’t find the Raspberry Pi.
for your information here is the output of arp-a command: