normally one can manipulate things by lifting the bucket and using tilt to adjust things
the top of the quick attach does NOT always fit super flush or tight on buckets or implements, and its not needed too to work correctly
they are this way due to every manufacturer quick attaches are NOT a standard size, they vary from size of height/length and width on different machines and brands
so
if you got this bucket some how twerked/twisted to BIND on things
again, try just using machine to lift and your tilt option to add pressure to try and level things, and or also drive machine backwards or forwards dragging bucket maybe to again use some force to un twist things
might even need to get something on one side of bucket to get it higher than other side to do this,
or find some un even ground so pressure can be applied where needed! you can also add oil to the top of the quick ttach too, to help it slip in the right way!
once you do this it should alleviate pressure on pin so you can lift it up all the way!
and like said, use a bunch of oil and keep these levers grease well and often