I've referred someone but my referral credit isn't working

Updated 

When your referral coupon has been used successfully, you will usually receive an SMS to confirm the referral has been added to your account. If you haven't received this yet, please check if the person you referred has already placed their first order, satisfied the terms & conditions and it's been over 24 hours. If this has been followed correctly, please place at least £25 worth of items into your basket (Please note, tobacco items are excluded from this offer). Before checkout, you should see the coupon auto-apply to your order.