Can someone please fix this code?

Question

Q:
To design an algorithm to fix elements of array and
permutes the remaining numbers using an efficient heap
sorting technique

Basically, I have to show all possible permutation
of an array by using heapsort.
I tried swapping parent and child element but there seems some mistake. Can someone please fix this code?

https://code.sololearn.com/c9KQIUBUb7yE/?ref=app