Technician reported not complying with MEL procedures for engine anti ice deferral; resulting in a rejected take off and a return to the gate for maintenance actions.

Narrative

Aircraft X arrived as flight from ZZZ. The flight crew reported the right Nose cowl anti-ice valve illuminated in flight. Company Maintenance Control was notified and the decision to place it on Mel 30-00-XX-X; with associated Mel 36-00-XX. The AMM references were received and the right engine was opened to lock the nose cowl anti ice valve in the open position and the high stage valve in the closed position. The AMM calls for the cannon plug to the TAI (Thermal Anti Ice) pressure switch to be disconnected. While in the process of completing the MEL procedure I was receiving maintenance call from our other business partners. I disconnected the cannon plug for the anti ice valve instead of the pressure switch. The high stage valve was locked closed and engine cowls closed. The log book signed and aircraft released for service. The aircraft left the gate and returned to gate after EICAS warning. Upon arrival back to gate the right engine fan cowl was opened. The anti ice valve cannon plug reconnected and the TAI pressure switch cannon plug disconnected per the AMM. The engine fan cowl was closed and the logbook signed. The root cause for this incident was the distraction of the incoming maintenance calls and not going back three steps to make sure the proper cannon plug was disconnected. The aircraft left the gate and the fight arrived to ZZZ without further problems.