I assume you mean you are getting a lot of pitching forward and back for want of a better description.
If you are not using a weight distributing hitch that could be the cause. The spring bars tend to eliminate a lot of pitching. If you are using one you might try taking up one more link.
Many people don't bother with the WD hitch on a small trailer, but it will smooth out the ride
Rick Davis 1602 K8DOC
61 tradewind, plus a few others
13 Ram 2500 TD
99 Dodge TD 577K miles