Husqvarna GT2254 gears grinding when shifting

Hi everyone! I have a Husqvarna GT2254. I've had a fair share of issues recently. A month ago I replaced both the drive belt and belt for the blades since it was loose and past due. All fine and dandy. Today a pulley mount broke due to rust and I fixed that.

Everything seemed to be fine but I noticed last week it started to grind when I try to shift into different gears from a complete stop. It still went in since the grinding was ever so slight and no force to put it in. Today, it grinded so much to a point that I cannot switch into ANY gear unless I fully turn off the engine and wait a few seconds, then shift it in. I am a newbie with this stuff but do have some small understanding. I don't know what is causing it to grind or what to look for. If I may also add, the mower does brake but it feels like it brakes on the last few hairs of the pedal fully pressed.. and sort of kicks when I let go. Not sure if that has anything to do with it.

My main concern is just the gear grinding right now if anyone has an answer. I don't have the mower in my possession because it's at my grandparents which is an hour away. I typically go there on weekends to help them out.