Where can i file a compliant on Clear Tax ?

I availed the clear tax services to file my ITR last year. the process was incomplete, and I was told by the assigned CA, he would take care of the rest of the work. Technically he missed filing the previous year ITR, I didn't pay attention to it, as I was dealing with some other stuff. Now I have to file the ITR-U, and have to pay the penalty for missing it.

I raised the request to the clear tax, even after multiple follow ups over email. They are un-responsive.

Where / how can I escalate this issue ?