Just installed inSSider and can't log in

I just installed inSSider (on 2/18/2024) with a fresh download from your website, created an account, and verified the resulting email query. When I cranked up inSSider, I got the log-on screen. I entered my email address manually and did a cut and paste of my password so I wouldn’t screw it up. No joy.

I got an immediate message that said "Unable to verify your credentials. Please verify your email and password and try again. So I did. My email address is correct. My password is correct (I clicked on the eyeball icon to make sure). Tried again half a dozen times and still no joy. What is it they say? “To continue to do the same thing over and over again while expecting different results is the height of insanity.” So I’ve stopped.

Obviously I’m able to log into my account on the website or I wouldn’t be here now. But I didn’t install inSSider to have another forum site on which to entertain myself. That desired purpose is being stymied. How do we fix this?