Rewrite the following sentence to match the tone of inquiry.
I don't understand why my assignment was rejected.
May I know the reason why my assignment was rejected?
Complete the following task based on the instruction and optional input provided.### Instruction:
Rewrite the following sentence to match the tone of inquiry.

### Input:
I don't understand why my assignment was rejected.

### Output:
May I know the reason why my assignment was rejected?