Dual dry clutch transmission then suddenly the transmission slipped?

I had drive my car listed above dual dry clutch transmission then suddenly the transmission slipped. I have the car listed above with 1.4L multi air turbo. I bought the car from somebody he didn't tell me there was a problem in transmission. I drive the car for 3 months normal I didn't face any issue after 3 month the car transmission start slipping; when it slips, I put it neutral for 10 minutes then it goes normal everything if slip I do like this suddenly it stop change gear and become slipping and appear on dashboard "service transmission " No Gear Available ". I went to Mechanic he opened the transmission, and he told me to change the disc and pressure plate. I did that, then he try it he found that still the same problem I took the car to another Mechanic he scan on OBD scanner he found there is lot of problems in wiring and solenoid. He arrange all wiring problems and changed 2 pieces of solenoid and changed the transmission oil, then he tried the car he found that the transmission start spit but not worked. Please need some help to solve the problem. Note that the transmission is dual dry clutch. Thanks