Connecting Ceiling Fan
If both switches are not working correctly someone messed up the wiring! We will need a schematic to figure it out. 

A schematic is a explanation of the wiring in each of the switch boxes and at the light fixture. 

Many times it is a simple screwup when a new switch was installed the person swapped the common with a traveler . 

We need pics or a full description, but can help, @harper has some good 3 way posts if you don’t want to provide photos reading up on one of these will give you a path forward.