Your question implies that you have a top load washer that has a fabric dispenser on top of the agitator. You can pull this type of fabric softener off of the top of the agitator to clean it. Most softener dispensers will just pop off when you pull upward. Once you get it off, you can rinse it with hot water. This should remove the softener residue that is likely clogging it. Some softener dispensers can be pulled apart for more thorough cleaning.
If you have a front load washer, you can normally pull the dispenser drawer out and clean the entire dispenser assembly.
If these tips don't help, refer to the owner's manual for your washer for directions on cleaning the fabric softener dispenser. If you don't have your manual, you can normally find it on our website by using the Owner's Manual Search feature. Click on the "Manuals" tab at the top of the page to access this tool.
I hope that this information helps. If you need more assistance, reply with additional details and the full model number of your washer.