Since we started building our robot we found that it is quite hard to get up the ramp.If any team has any idea how to,we would be more than happy to help any team willing to help us.Thanks in advance-HBS Enigma
What is the main issue you are experiencing… lack of traction, wheels falling into holes, etc.?
Most likely cause is lack of traction
General tips: If you are using omni wheels, then try switching to rubber tires. If you are already using rubber tires, then try doubling them up. Keeping the weight of your robot (brain, motors) over that wheels that are powered will help. If only two wheels are powered, then try powering all four. Try a lower gear ratio (more power). Stay away from the holes on the ramp. 
WE USE TIRE TYPE TANK AND CHAIN
Good to see a UK team on the forum! Maybe post up a picture of your bot. For the robot we built for the BuildBlitzUK, we had 2 motors, 4 wheel drive via chains. Rear wheels are standard 200mm travel, fronts are omnis. 1:1 gear ratio. Quite a big heavy robot, no probs getting up the ramp. However, the weight may actually be helping keep traction.
Something else to think about, you don’t want the weight over the front wheels when trying to drive up the Ramp, you want weight evenly over all 4 wheels or slightly biased to the back.