Sealing, or an Expungement, is controlled by State statute. Unfortunately, you do not list what State this occurred in, so there is no way to answer your question accurately. In general, a State typically imposes a waiting period after the completion of the sentence (even for a diversion disposition) before you can even start to apply for this type of relief. I suggest you contact a criminal defense lawyer admitted to practice law in the State where the charge was filed and ask them the question. In my experience, most lawyers are willing to answer these types of questions without charging a fee. Good luck.
This answer does not create an attorney-client relationship or constitute legal advice. Given the nature of this website, it is provided solely for informational purposes, for you to use as a starting point when speaking directly with a lawyer in your State. Do not assume that the legal theories I mention that pertain to NJ will apply in your State. I urge you to immediately contact an experienced criminal defense lawyer admitted to practice in your State before making any decisions about this case.
I'm assuming you received this charge in Ohio. Some diversion programs automatically expunge records upon satisfactory completition. So first, make sure it hasn't already been expunged. But, yes, you can ask that record expunged. Consult a lawyer.