Sometimes when trying to sign in to online resources through the library website you may get a 400 error which reads something like "Bad Request. Your browser sent a request that this server could not understand".
The most common solution to this problem is to clear your cache and cookies within your browser history, below is a screengrab of what this looks like on Google Chrome (make sure and set "All time" as the time range). For other browsers just google how to clear the cache on that particular browser.
Another solution may be to try using a different browser than the one you are currently using (Chrome generally works quite well).
If you are still having difficulties having tried the above feel free to contact the library and we will try to find a solution.