I live on the ground floor of my home and rent out the top floor.its an older home.

I have recently installed a hung ceiling with insulation in between all the joists.

here is the problem,when the people living up stairs walk around it sounds like they are stomping on the floor/cieling.
I thought the problem maybe the fact that the joists don't have any cross bracing.I have try ed putting in a few cross braces in between the joists to stop them from moving but now the floor/ceiling squeaks and walking on the floor still sounds like they are stomping around.

can anyone make a suggestion on how to solve this problem?? or tell me how to reduce the noise from up stairs??

You would need to put something under the hardwood floor upstairs to reduce the noise. Unfortunately you can't do that so you'll have to live with the noise.

True Hardwoods - Hardwood Floors

Carpet on floors upstairs will help a lot.
You can also install sound proofing sheetrock. This stuff is expensive about 40$ per sheet. It should be hung on metal Z shape brackets to dampen the vibration caused by the walking around.
Cross braces help prevent movement of the floor, but will do little in stopping the noise.

Sound is transmitted several ways. The insulation you installed might not have been sound-absorbing insulation, which is more dense than thermal insulation, so it may not be doing its job. However, sound will be still transmitted through the joists, and that can be mitigated by installing a gypsum board ceiling, as Home Crae Club has said, on the resilient channels. The thicker the gypsum board the better, and the sound-absorbing board is an option also. But, as HCC also said, the quickest and easiest fix would be to install carpet on a good pad upstairs.