Do you have drain holes in that current container? If not, your plant is maybe suffering from root rot and that will kill your plant. Transplant a.s.a.p if not in a container with proper drainage.

If it isn't the container, the next problem could be underwatering or overwatering. You must give us more info. for a proper diagnosis.

Only water when the soil is dry. Do not water so much that the soil is mucky/muddy. Dip your finger about 1inch deep into the soil. If it is moist underneath, do not water.

Just so you know, the top soil will appear dry at times, but always do the dip test to make sure.

Peace