How can I navigate the theft charge levelled against me ?

Dear Sir, In a recent accident, one of our Boss Lost his wallet.from our store while there was a training program. so we search the whole place and shown even the bag also. and the day after that,one boy came to me which i don't know him and ask me are you from that where the training was taken ? i said yes and he told me that he found some card from under the pillow and i wanted to check something on it. So , i said OK and went to an ATM. as soon as we reach the ATM, he ask me to wait there saying he will be back soon. and when he came back, he gave some cards with a small piece of paper with a 4 digit and ask me to go in and swipe the cards he said he has swiped some cards. so , i went in and swipe them. after i came out and says it was not working, he told to give the cards to our boss but i refuse and i ask him to give it yourself but he refuse so i went to my store again, After some days our boss called me and ask me were his wallet was, and i told i don't