Haven't received my vbucks and it's been 2 weeks.

Hiya!

Paul from the Xbox Forums Team here to assist, it sounds like you're talking about the recent promotion we had available. Have you tried checking your Xbox Messages for a message regarding the Vbucks? As well here are the terms and conditions for the offer.
Terms and conditions

Valid only for new subscribers or users who canceled their subscription before 10/1/2018. Limit: 1 offer per account; credit card required. Only valid through link in this offer, in all Xbox Game Pass markets excluding Quebec. After first month, subscription
continues to be charged at the then-current regular monthly price (subject to change), unless cancelled. Plus applicable taxes. Game catalog varies over time. Not valid for existing subscribers . After promotional period, subscription continues to be charged
at the then-current regular monthly price (subject to change), unless cancelled. Plus applicable taxes. Limit: 1 offer per account. Only valid through link in this offer, in all Xbox Live markets excluding Quebec. Credit card required.

Happy Gaming!

Paul Xbox Forums Team!

Its been two week still havnt received my vbucks

Didn't receive my vbucks promotion after 2 weeks and a day. Help.

I haven't received my free vbucks

If you're referring to the offer to receive vbucks when you purchase a 3 month subscription, it takes up to 2 weeks to receive the code.