@AhtishamAshraf (1) Your project is a bit advanced, because it involves three things, RFID, Relay, and Door Lock. I guess only less than 1% of the readers in this Rpi SE and EE SE know what is going on! BTW, our comments in your question section got too long and so the Mod set up a chat room for us, so other readers might us too long winded. Now we have already an answer, I think it is OK for us to comment below my answer, until our comments get too long, and the mod would act again. Cheers.