peerless mst206 2nd gear and reverse not workin

so when ever I shift into R it engages and then disengages same thing goes for 2nd gear its weird like if it wasn't engaging all the way almost like a slip. has anyone else had this problem ???

Maby the teeth are half way ripped off, check that

i did open up the case not to long ago to change the oil. everything looked fine tho, but since then its been doing that. i have a feeling it could be my shift lever not engaging all the way its the murray shifter with like the teeth on a bracket