It was off yesterday so i couldn't reply , i will check and debug it today. Do you have any code for the Solenoid RFID in Python? I will check that code and will compare it with the code i am currently using @tlfong01 and thanks a lot for putting this effort and debugging the issue.
@AhtishamAshraf As I said earlier, take it easy and no hurry at all. Actually I have not been doing RFID and relay programming for more than a year, so I need to read my old post to freash my memory. Below is a short YouTube list I am now watching.
(1) back emf test 2019mar3101 https://www.youtube.com/watch?v=MDQ6ObyIy2c
@AhtishamAshraf Take your time. Ah, my time for lock down jogging and supper. See you later. Cheers.
Ah, I forgot I let you know that my "solenoid door lock" is using the solenoid core to pull a string to open the door for my cat, wearing a RFID tag, can come in.