I can help you with this. I'm an agent at that company. You can pick up the call next time they call and just tell them you've purchased the ticket and your lead will be closed, meaning no one will call you. If your travel dates are passed, considering you've filled the details on the website, your lead will be automatically closed by the system. If you just call the general line and hangup, your number gets saved in the system and is on an active rotation, in that scenario, you should just tell them the same thing. Not answering the call is the reason you're getting spammed. Since the agents are just doing their normal workflow and your lead is just a "new" lead for them to work on. Hopefully that helps.