To reiterate:
Expedia is not involved in this scam. Scammers are posting phone numbers for airlines and for travel websites for customer service to get people to call them to make flight or travel changes and then they charge exorbitant fees to the people who were duped while pretending to be the actual travel companies or airlines.
Here’s an example and a Reddit thread about it:
https://www.reddit.com/r/Scams/s/49chKYk9uG
If you are booking travel and not sure about something that requires customer service, please post here or in a place like Flyertalk where there are a lot of experienced travelers that can help you find legit customer service. Or at the very least, access customer service numbers by finding ones listed on the company’s own websites.
Don’t rely on AI or Google results that may spoon feed you to scammers!