Read the terms and conditions.
Airlines have sucked ****’s with pointy teeth since 9/11
Agree to it and there is little you can do, but wiener boy found a way.
I did. Did you?
Here they are... and rule 21 appears to be the section that would govern this and I can't find anything that supports the airline's actions... can you?
https://www.united.com/web/en-US/content/contract-of-carriage.aspx#sec6
If you can point to something in this contract that justifies what UAL did then I will gladly accept what you say as being true. Will you also vow to admit that you're wrong in this if you CAN'T find what you claim is there?