You need to dial the Swiss Airlines phone number to get in touch with the airline on the phone.

Here are the steps below:

Search for the official number of the Swiss Airlines
Dial the same number on the phone & wait till the call connects
You need to listen to the IVR voice & thus follow the instructions
Here, you'll learn about the relevant number & connect with the Swiss Airlines customer manager on call.
Now, tell them about the whole problem & get the solution from the other side.
They'll explain everything to you, which will help you with the flight booking.
Visit: https://velog.io/@3456234/Guide-to-connect-with-a-Swiss-Airlines-live-person
Source: https://manageairlinesbooking.com/blog/how-to-talk-with-a-live-person-at-swiss-airlines/