First of all, were you using CVX 2.2? If not do so. Do not use CVXQUAD with CVX 3.0beta.
Second of all, you can try my advice at I am not able to solve this . (except update the advice to use CVX 2.2 rather than CVX 2.1).
If you still encounter an error, and you are using CVX 2.1 or CVX 2.2, perhaps you can provide a complete reproducible problem here or at https://github.com/hfawzi/cvxquad/issues
The most reliable and accurate option is to use CVX 2.2 with Mosek 9.x.