Do you mean you have a high cylinder? Do you know what brand contact you used? Lenses can rotate due to eye movement so sometimes getting a stable fit can be tricky. A back surface toric will usually stabalize fairly well since the cylinder on the lens is on the back surface and should lock into place with the cylinder on your cornea. There are also different prism ballast designs so it may be worth trying a few different brands. Also, if the cylinder is very high you will have to get a custom lens to get the best correction since most manufacturers won't keep an inventory of very high cylinder lenses.
I'm not sure undercorrecting the astigmatism in your eye would help much. It could be that you have more lenticular astigmatism and not as much corneal astigmatism. In that case, it's possible that lowering the cylinder on the lens to match more closely what's on the cornea might help with stability. Corneal astigmatism is more common however.
Another important thing to consider is the base curve of the lens. Tightening up the base curve may help reduce movement of the lens but if it's too tight, the lens may vault the cornea giving poor results. Best that the doctor consult with the manufacturer on what the best base curve to use for your eye is.