False advertising

So i bought the cosmopolitan magazine for my girlfriend which had a Rain 4G sim card. The simcard had a sticker displayed "Activate SIM NOW, get FREE Unlimited data for first 7 days". This required me to log in to their website and rica the sim however i was expected to choose a plan before i can RICA and pay for such plan. Now i couldn't get hold of them on their customer care line most probably due to LOCKDOWN but I still need answers. How do i get my free 7 days unlimited data or refund for the money paid on the plan i chose as i feel i was only supposed to pay after the 7 days trial period.