6 cta fuel shutoff solenoid

Replaced my fuel shut off solenoid 7 months ago. Flawless till now. Occasionally key will not shut off the  engine. Ordered new one and replaced. Same part but won’t fire engine at all. I replaced with the old solenoid and she fires right up but occasionally will not shut off until I go below and push on the fuel pump arm. Not sure if I just got a bad solenoid or I have a deeper issue. Any help would be great.

thank you