Code P2096

Hi , my car was doing well, but i scan the efficacy of catalytic converter using my own obd scan tool and showed sinusoidal wavy graph of s2 o2 sensor in bank one. so it is bad catalytic converter. i took it to one who assume that he can clean it. i cleaned it, but after one hour of driving check engine light come and a code P2096 appeared. i check it and obd tell it is a converter or o2 sensor problem. i removed the check engine light and i drive it again and the not appeared again. i plugged the live scan obd to see the voltage of o2 sensor S2 , and showed abnormal graph in which at begin low voltage then within seconds reach fixed high voltage? I change it from wavy line to fixed high voltage line, is this danger?
What can i do ? Is it urgent? I attached the new graph. please help what to do?