Help With A Value Issue?

RN.Value = (math.random(7))
if RN.Value == LRN.Value then
    print "Same Number!"
    while RN.Value == LRN.Value do
    RN.Value = (math.random(7))
    end
elseif RN.Value ~= LRN.Value then
    print "New Number!"
end
print(RN.Value)
LRN.Value = RN.Value

RN = Room Number LRN = Last Room Number

That script above is made so that the same room number can't be generated twice in a row. If it is, it's supposed to keep generating numbers until it gets a new number, but it doesn't work. It always prints 'New Number!' even when it's the same number as last time. Can someone help me fix this to work properly? Thanks.