Air Carrier Flight Attendant reported a fume event during descent characterized as strong musty odor in the forward cabin area. First Officer and flight attendants reported experiencing physiological symptoms once parked at the arrival gate.

Narrative

We had just prepared the cabin for landing when we all got a call from the flight deck. I was FA (Flight Attendant) 04 on a 737 so my jumpseat does not have a phone. FA 02 told me that the FO (First Officer) was feeling nauseous and requested a sick bag. FA 01 and FA 03 secured a cart up front and passed an empty trash bag up to the flight deck. The flight deck asked if we could smell any strong odors in the FWD cabin; LAV; or Galley. All four of us (FAs) went to the FWD lab and galley to smell check; it smelled like a strong air freshener to me. FA 02 admitted that she got light headed after smelling the strange smell and we then went to our jumpseats. After landing and the flight deck door being opened; FA 01 and FA 03 say that they could smell the strong musty odor that the pilots were complaining about. The pilots had to open the windows in the flight deck once parked at the gate to air out the strong smell. I did not have any signs of discomfort or injury except for pain in my right arm and slight twitch of my right eye.