Citizenship is not a right or an entitlement. It is also not an immigration application. What might have been accepted for ilr, will not necessarily be accepted for citizenship.
If you overstayed and work illegally, you were in breach of the rules and had no regard for the laws of the land. Simples.
Char (CR001 not Casa)
In life you cannot press the Backspace button!!
Please DO NOT send me a PM for immigration advice. I reserve the right to ignore the PM and not respond.