My 2 cents worth
If you are using an Apple IOS device version 14.xx (Iphone and Ipad) its necessary to go into the IOS settings and change the privacy setting. ? On Windows 7 my putty.exe was pretty old so it was updated and that fixed the connection problem.
The very very latest IOS 14.nn+1 update kills a lot of our favorite programs for remote control and I¡¯ve not yet found the solution however WEB based apps like Astroberry and the CSN Satellite controller work fine because we use a web browser to access them. ?
Bill P.