programs net cut and change MAC address

I am using the Microtek successfully hide the Mac and IP address of all users but I have users who install IP through that procedure appear to Mac users for the rest and adores easy time changing the MAC address and steal from another user, use the load quantity set for it and be contacted by telephone from the user which was stolen and I’m embarrassed because I don’t have a definitive solution to the problem I hope Messrs. expertise and solutions to problems cooperating with me
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