@Carly145
I am sorry to hear your experience.
Do you mind to share in the CC -
Did you made the cancellation before you left?
Did the host mention in the listing announcements described the apartment is directly next to the highway?
Did the host described “ Potential of noise” in the “ Things guest should know” section ?
-In case, the listing announcements lack of above information, you should be reasonable to get back the refund.
-But if the listing did mentioned above point, you didn’t read well the announcements and make the booking.Subsequently, you may can’t get the refund.
-On the account of this, you can explain to Airbnb case manager that you didn’t notice in the description, you can still negotiations with Airbnb demand for the refund.
As a matter of fact, any incident happen guest be obliged to report to Airbnb, “ Live Chat” with the CS though Airbnb Support Help Center, request the case manager to cancel on host behalf, refund the full payment and help to relocation you to the new place immediately.
Beside phone call, did you try " live chat " with a CS? ( not an Airbnb bot)
Usually, you will have an answer from them within minutes.
In addition, contact Airbnb via social media Twitter, Facebook for attention with fast respond.
https://community.withairbnb.com/t5/Help/Contact-Airbnb-A-Community-Help-Guide-UPDATED/m-p/413245
I hope you can resolve soon, and get back your payment.