Seems like ioffer doesn't really have a nice reputation in general. If you do a random search on Google ioffer+scam you'll be amazed with all the negative posts and reviews about them.
Rule of thumb is to check the seller's feedback, you'll have a relatively better chance of receiving real products from sellers with a lot of feedback. A few have suggested to just buy the product elsewhere.
To avoid being scammed when shopping online, please check out this article and take note of the points and tips that will help you spot a scammer - Link hidden: Login to view
Hope this helps :)