I found landings pretty tough at first, I was fine with one instructor but with the other I just couldn`t nail it because he always seemed to be too keen to 'help out' on the landing. The solution was to stop flying with him completely. The next week I was off on my own
Another tip that has helped immeasurably was to not have a death-grip on the yoke. My instructor had me wiggle my fingers on the approach to relax the grip I had and my landings immediately improved because I wasn`t overcorrecting as much and making a hash of it
Good luck and don`t give up
cheers