2001 Volkswagen Jetta P0302 code on my Jetta 2001 AZG

Suddenly my car started to stumble and hesitate. Check engine light was flashing then remained constant. I took it to a local mechanic. And he told me that Cylinder #2 is misfiring due to a problem in the ignition cable. Then He replaced the spark plugs as well as the ignition cable. Spark plugs he installed were bosch with 2 head platinum. After that my car was fine but on idle it was not smooth I can notice some stumble. And once I kept it parked for 2 days then when I tried to start it was having the same symptoms as before along with the same code. I took it to the same mechanic and he added some injector cleaner liquid in the gas tank. Even before pouring the injector cleaner detergent the check engine turned off by itself when I was at the mechanic shop which was so strange. Again same thing. What I noticed is when I don't use the car for some time this problem comes.

After couple of days the same problem came I took it to the mechanic and he said that the coil pack needs to be changed. He tried to find a matching coil pack for my car but didn't find one and he advised me to take it to the VW Dealer. I took it there then they said it is having a bad wiring which feeds the coil pack they got that cable replaced which costed 40$ parts and 325$ labor and diagnosing fees. I parked the car for 2 days for testing purpose and the same problem came, I took it to VW dealer and this time they said coil pack is cracked and needs to be replaced but they waived the 110$ diagnosing fee coz before they didn't fix the problem I paid 558$ for it to be replaced. But still I can feel it stumbles on idle. And I don't feel it is fixed currently I am parking it for almost a day and wanted to see tomorrow if the same problem is still there. I asked the dealer whether the fuel pump could be the reason but he said fuel pump will make the car not to start at all.

I spent more than 1000$ to fix this problem but still it is not fixed. Please I need any advice from you guys.