I am sorry to hear this happened.
Are you talking about buying a package of several tanning sessions?
And you asking just about the lotion being returned?
Unfortunately, the store does not have to provide you with it's return policy.
It's your legal obligation to inquire about their policy when you buy something from them.
And the store is not legally required to take back any product for a refund or an exchange.
So the only way you can get your money back is if you can take the position that you were mis-represented.
So if you were told that you were paying for 2 packages and lotion and you got one package and lotion you could likely sue them successfully for a full refund.
But if that is not the case then unfortunately you will not be successful in getting your money back.
However, sometimes threatening to sue them works.
You can call the manager and explain what happened and demand a refund and threaten to sue and you very well may be able to get a refund.
But if you do sue it will be your burden of proof to show that you were mis-represented.
That is a good point and one that you should absolutely raise with them.
You were led to believe you were getting two packages and not one and you never were given a proper receipt which shows how horribly disorganized they were because you were absolutely entitled to the receipt.