If you have a username like: RP Deliverance
And you want to sign in, it only allows you to type in: RP Deliveran
Take a look here:
admin panel --> configuration --> settings --> User Registration and Profile Options -->
Maximum Username Length
And how much is it?
Replace 12 with a bigger number.
RP Deliverance has 14 characters (if you include space too), while RP Deliveran has only 12, because of the limit.
How can i disable space, and special characters?