If you have or about to pay for flights or holidays via PayPal then credit credit card protection under section75 is unlikely to be covered
"You're usually unlikely to be covered when payments are made to a company that isn't the one providing you with the good or service because the credit card company must have a direct relationship for them to be equally liable.
The first main area is paying via an online processer such as PayPal, WorldPay or Google Checkout. Though these can have their own refund systems, they aren't as strong as the legal protection of Section 75."
from moneysavingexpert.com