D105 Stuck in Reverse

Help please!

I just got a D105 a few weeks ago. While mowing the lawn today, I put it in reverse and now can't get it to come out.

I tried pushing it to get it to come out, and moved it to level ground to try and get it out.

It won't start on its own, but I jumped it and it runs fine. Moves in reverse with no issues. But, I just can't get it to come out of reverse.

Any suggestions?