Try to solve problems that are a bit harder than you solve now. I see you solved more than 100 problems with rating 1600 and only 3 with 1800. And another important point is trying to solve problems without editorial. Maybe you don't know some well-known techniques (like binary search, but I think you do) that are pre-required for solving D2C-D2D. And in CFR it is very important to solve fast, but first of all you have to learn how just solve them.