PureGym Offer

I have seen that PureGym are offering 30% off (for 3 months) and no joining fee. I was thinking of rejoining, but cannot see how to get this offer to work. Has anyone else managed to do so as there seems to be no way of contacting them to work out. There is a big red banner saying "UPGRADE COMPLETE GET 30% OFF YOUR FIRST 3MONTH PLUS £0 JOINING FEE. HURRY ENDS SOON!" when I sign in, but when I go through the selection of a monthly package I cannot see the discount and it seems to want to charge me for the joining fee and normal rate?