Angela, This may not work for you, but I have a home steamer and use it to clean my oven. The steam cleans out all kinds of residue. I have a Sargent Steam, which is a powerhouse, but expensive. There are less expensive models that would probably do the job of removing residue, only a bit slower. Perhaps you can rent a steamer. I find that the included brushes that attach to the nozzle are awkward to use; I usually use the nozzle alone and a brush or cloth in the other hand.

Find out what they used on your oven. If they used oven cleaner, it may have ruined your self cleaning oven. If not oven cleaner and you find out what they used, I would e-mail or call the manufacturer of your stove.

I would be hounding the 'professional'. They should NEVER clean a self-cleaner like that! The surface of the inside of the oven is made differently and will absorb those chemicals. If the 'professional' cannot fix it, then they should replace it. You hired a professional for a reason. They should be bonded and insured, which will cover their losses for their mistake. Good luck to you. I would be SO mad!