Hello. Welcome to Just Answer. First, you should confirm that the setting of the 4 dip switches in the battery compartment matches the switches on the receiver. The receiver is located (typically) in the fan's canopy, which is the main wiring compartment, just below the ceiling.
If the switches are already matched up, then you most likely need a new receiver. You can get them at any home improvement store. But I prefer the Hunter brand products, which are available at Home Depot. If you want an exact replacement, which I would not recommend due to Hampton Bay's questionable quality, please let me know so I can give you another source.
Yes, definitely. I have installed all brands, and Hunter is head and shoulders above the rest. I'm sure all of the other electricians here would agree, if I were to ask them to view our conversation.