You’re describing this as a problem with both brakes, which would be rather odd. If it was just one of them, I’d suggest bleeding (though you probably need to do this anyway), but for both to do this, that’s strange. Has it started doing this suddenly or has the bike been left unused for a few years ?
Also check the alignment of the calipers. If they’ve been installed misaligned with the rotors and the pads have worn at an angle, this can cause drag problems. If it’s really bad, you might need to re-align the calipers (pistons parallel to rotors) and start with new pads.