Unfortunately this is one of the downfalls of being at the top of your server. I too have the same problems where I face teams 3-4 levels higher in the CL and Cup too. The same problem of being high up occurs in the League where you have the same opponents season after season. Tanking isn`t an option either as usually everybody levels up. I cannot see an easy fix for this in the short term and I sympathise with you. Stick with it, there are plenty of us in the same situation.