It appears scammers are calling potential victims from 855-977-1975 and other 855 area code telephone numbers pretending to be from United Airlines, offering them some form of refund. Therefore, recipients of calls from 8559771975 are asked to take precautions and should never disclose their financial and other sensitive information over the phone. If you have any information about 855-977-1975, please share it in a comment below.