Change of Status Denied Due to Expired I-94

my COS application has been denied because my I-94 expired more than 30 days before the start date of the study program as listed on the I-20.
my I-94 expired on the May 27th, the original I-20 I got had April 25th listed on the I-20, there was a mix-up and the school gave me an I-20 with June 29th as the start date.
USCIS got my application on May 11th, and I got a denial on Dec 17th, no option to appeal only motion to reopen or reconsider.
I would like to avoid leaving the U.S and waiting and starting all over again, what are my options? should I file for MTR? on what grounds? what are my chances?
what are the implications/ramifications?

You have been illegally present for over 6 months likely triggering a ban for at least 3 years. Discuss your situation with an immigration attorney as you prepare to leave the US.