I have tried clearing my history to remove an incorrectly keyed login but it won't disappear and when I try to key in the correct login, it automatically thinks I want the earlier one and selects it for me so I can't login to the site!!

I just registered on a site with the login leigh110174 and when I went to log back into the site, I inadvertently typed Leigh110174. Now when I try to correct the logon to leigh110174, and then tab to the password field, it autocorrects to Leigh110174 and I cannot change this. Each time I correct it to lowercase l and nagivate to either the logon button or password field, it auto corrects to the uppercase L, which means I cannot log into this site. I have cleared my recent history (last hour as I been on the pc less than an hour) but this did not remove the auto pop up or help at all.