You will need to double-check the documentation you received from the court and signed. If you applied for, entered, and successfully completed a diversion program, the case against you should have been dismissed. If this case appears on your criminal record, it is either because you did not complete the diversion program, the program is still pending (some take around six months to complete), or you have a similar crime in your past.
Also be sure that the record states that you were adjudicated guilty, and not that you were merely arrested for an offense: There is a difference. An adjudication means a judge either found you guilty of, or you entered a plea of guilty to, a crime. An arrest record simply means that you were arrested on suspicion of committing a crime, not that you were actually guilty of the crime. Thousands of people are arrested for acts they did not commit, but those arrests do not always end up as convictions on their criminal records.
You may want to consult with a criminal defense attorney to review your record for any mistakes.
Best of luck to you.
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If you entered the pretrial diversion program AND successfully completed it then the case should have been Nolle Prossed (Dismissed). This is likely what happened because if you were bounced out of the pretrial program then you would have received a notice to return to court to address the original charges.
I think you may be confusing the word 'conviction' with the fact that the record of your original arrest is still visible. Assuming that you successfully completed the pretrial program... then in order to erase everything from your record, you would need to take an additional step and have the case expunged. Expunging a record is possible only if you have never been adjudicated on any other crime (felony or misdemeanor) and have never sealed or expunged a prior record.
A quick review of your actual record would allow an attorney to see whether or not you were eligible to expunge your record. I have also attached a link below that details the process. If you are interested in reviewing your record and expunging it if possible then feel free to contact me.
Best of luck.