help bottom braket

Sam12

i have hollowtech 2 cranks (lx)i have a race tommorow so needs fixing fast i can not take it to my lbs.the bike is 5 weeks old and i have done about 200miles on it i mainly ride xc with some very small jumps.any way i just got it out to check it and put some oil on the bike then i rode it and when both cranks are neutral it thumps.can you help me fast or give me any advice

supersonic

You need to try and explain the problem in more detail.