Contractor did not pull permits-Ohio

[Katie Shepard]

What happens to a contractor if they did work without a permit?  Is this just a slap on the wrist, or bigger fine/punishment?  We have a contract with a licensed contractor and he owes us approximately $10k back from our initial deposit of $28k.  We've not heard back from the city (they are super slow due to covid) and I'm trying to figure out if we need to take legal action. Any insight or advice would be awesome!