Trouble Registering CS6 On My Adobe ID Account

Hi there, I'm new to this and I am hoping some of you can help me with my question. I recently bought a copy of CS6 Master Collection from an online store that had advertised the product as new. I tried to register the serial number on my Adobe ID Account but I keep getting a message telling me that the product has been registered to another user. I contacted the store to explained the situation and asked them for an unused serial number. Their reply was this:

"We have encountered this issue before with serial registration of Adobe CS Products. This is occurring cause Adobe is holding registration for all CS products for last few months and when Adobe will resume the registration you will be able to register this product under your Adobe account. All serial numbers are showing this same message for all CS version. You might have noticed that, while installing product, it asks for serial number and Adobe account. If it was registered before, it would never be installed and you would see the error message instantly on installation. We have tried to contact Adobe and didn’t get any satisfactory result. We presume, they are holding the registration for boosting up the sales of CC subscription version. Please Don’t worry, you won’t having any issue with the product as we are registered company and we will solve any issue."

Can someone please tell me if this is correct, or has the store provided me with a serial number for a product that has already been used and registered. I have not made any attempt to download, install, or activate this product as I wish to register the product to my Adobe account first. I appreciate any and all answers. Thank you in advance.