I booked a double room at Guilin Hongfeng Hotel, 15th on May, but I don't know what floor it's on. The phone number listed for Hongfeng Hotel in my message is an invalid one!

If it’s booked through Ctrip, you can call the Ctrip customer service hotline to contact the hotel.
You can contact your reservation channel or query the hotel phone number through 114.
If it’s booked through Ctrip, you can call the hotel’s front desk to contact Ctrip customer service.
You can contact your booking channel, or dial 114 to query the hotel phone number.