momentum and collisions

if a hard sticky mud ball is trown on a wall it sticks to it
it is an inelastic collision
K.E. is not conserved
but here momentum is also not conserved because mud had an initial velocity
so initial momentum of mud + initial momentum of wall (that is 0) = initial momentum of mud
final momentum of mud (that is 0 or less than its initial momentum)+final momentum of wall= 0 or less than total initial momentum
please explain hiw momentum is conserved here??