If we mention the long story short, yes, most are eligible to cancel the United flight and obtain a refund. But, there are certain conditions applied to that, these are:
First, If we cancel a flight within 24 hours of booking, then we are eligible to induce the complete refund within the original form.
Second, If we cancel a flight after 24 hours of booking, there's an exact amount of fees that's deducted from the booking charges.
And for further assistance regarding any issues with United Airlines Flight Cancellation Policy or refund, the customer can contact the assistance desk at United Airlines.