Is it legal to file a memorandum of agreement on an assignment contract (Ohio)? Seller is trying to raise the price and sell the property and cut me out. HELP!!!

Memorandum of agreement? Do you have the property under agreement or are there still basic terms still left to negotiate? Are you licensed as a broker/agent?

You will need to talk to a lawyer in your jurisdiction, because if they are trying to cut you out of a validly enforceable contract you may be owed either damages or could seek specific performance. There are so few details in your post on your situation though that it's hard to say.

@Earl Marshall

Look at agreement and see if it says you can’t record it. Otherwise I record the document especially if money has transferred. Let the judge decide. 

ok