Unable To Update GarageBand After Switching Apple ID
When I purchased my computer, I signed in under a shared Apple ID, under which the standard-issue Apple iLife and iWork programs came free. I recently switched to my own Apple ID, but found that when prompted to update GarageBand from within the software, I was prompted by the Mac App Store to purchase it for $4.99. When I logged in using my old Apple ID, I was confronted with the same scenario. Is there perhaps something I was doing incorrectly, or are there other steps that I must take in order to get the latest version of this program? I am aware that programs are tethered to their original purchasers, but that doe snot explain why I was unable to update under the old Apple ID. I even went as far as to delete it and tried to "re-download" it, but I would still have ad to pay $4.99 (following this prompt, I recovered GarageBand from the trash).
Assistance would be greatly appreciated.
MacBook Air, OS X Yosemite (10.10.1), Mid-2013 13"