are they the same shape?
if both just got an R on them it's likely a misprint
if both speakers was connected to the right channel output it would 1/2 the sound compared to if they were on left and right
you can test them easy by connecting them to a computer where you can control the balance between left and right if both play in R then you have a problem if one stop playing when you only only play out of one of the channels they it's a missprint on the headset
just in case you didn't knwo then it's a 99% risc that your gifted headset is not made by apple and if they claim to be it's a copy product