@Vu25 Airbnb customer service is in terrible shape right now, so you will just have to be patient and persistent. I can't see why you wouldn't have been eligible for a full refund when cancelling within 48 hours of putting in the request if the dates are 2 weeks away and it was only for 1 night. If you are still within that time period, you should go ahead and cancel, and I think you'll be refunded.
As a guest, if you have questions or things to work out with a host before committing to a booking, you need to send an Inquiry, not a Request. You send an Inquiry by clicking on the "Contact host" just below the listing description. An Inquiry doesn't obligate you in any way, even if the host pre-approves you- the guest actually has to take the next step to go on to book, rather than their card being charged.
If you send a Request, as soon as the host clicks on Accept, you'll have your card charged. And hosts are required to either Accept or Decline requests within 24 hours, so that puts pressure on the host when you may not have had all your questions answered yet, or the host have gotten answers to their questions of you.