Having more than one adwords account can get you a permanent ban from Adwords & Adsense, basically their whole ad platform, if it was me I would get a friend to create a new account, someone who will never use it and use the voucher …
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£75 adwords voucher
Tags: a-new-account, adsense, and-use, basically-their, get-you, new-account, the-voucher, voucher, will-never