[Dignity]

I'm not really sure what's causing your error. I'll try to help though.

Can you try changing

pawn Code:

else if(dialogid == REGISTRATION_MENU_ONE)

to

pawn Code:

if(dialogid == REGISTRATION_MENU_ONE)

EDIT: If that doesn't work, use a different method of reading dialogids:

pawn Code:

public OnDialogResponse(playerid, dialogid, response, listitem, inputtext[])
{
    switch( dialogid )
    {
        case: MAINMENU2
        {
        // code
        }

        case: REGISTRATION_MENU_ONE
        {
        // code
        }
    }

    return 1;
}