Glitch In Parkour

So, I have had this issue multiple times. When I leave or complete a parkour course, my inventory doesn't go back to what it was before, I still have the arrow, bone, sapling and book. What really set me to make this was the loss of 62 diamonds in my inv. I was wondering if I could get these back. Thanks yall

 

This is a very known glitch, if you ask a mod they should give you your stuff back.

 

ok thankyou!