We've experienced login problems with Paypal from time to time. It's very rare but can be frustrating to say the least and detrimental to our business at worst.
"Some information you entered isn't right."
If you keep getting the above error message even though you know your login credentials are correct, here's a tip that has worked for us:
Scroll down to the bottom of the Paypal screen and click on the Contact Us link.
Enter your login info at the top corner of that page.
That seems to solve the problem for us. You can also try using mobile if you have access, but be aware there may be some features which are not supported on mobile.