Two smartphones-only one connects with park wifi?

We ran into our first "case sensitive" login name (not password) 2 days ago. Never seen this before. Our Samsung S-4's refused to log on as they always "capitalized" the first letter of the user name. The net work, (Nellis AFB, Desert Eagle) uses all lower case. The "auto capitalize feature" in android devices can be turned off but it is inconvenient to do so, as well as to find in device settings. It took work (had to enter 2 "d"s and then delete the upper case one before it auto-corrected.
Bill