u could try this.
goto C:\Users\YOUR PC NAME\AppData\Roaming\Kodi\userdata
open profiles.xml or you could simply delete profiles.xml
look for <lockcode></lockcode>
update did some reading and it looks like it encrypts your lock code.here's part of a profiles.xml with no locks
edit your lock settings to below and it should remove the lock
<lockaddonmanager>false</lockaddonmanager>
<locksettings>0</locksettings>
<lockfiles>false</lockfiles>
<lockmusic>false</lockmusic>
<lockvideo>false</lockvideo>
<lockpictures>false</lockpictures>
<lockprograms>false</lockprograms>
<lockmode>0</lockmode>
<lockcode></lockcode>
also exit kodi,make the changes,start kodi.
Code:
http://kodi.wiki/view/Settings/System#Locked_out.3F
section 7.3