If you purchased your TV as a "Smart TV" then I believe you are entitled to change the TV for one that meets your original requirements, PROVIDED this was a fundamental feature of the purchase. The retailer from whom you bought the Smart TV is not at fault, so I recommend that you contact the manufacturer first.
I recently negotiated a Brand New Replacement TV direct with the manufacturer for this reason.
They start by offering a BlueRay Player to hang off the TV but disgruntled buyers should persist that they return the tv functionality to its state when purchased.
Their first line of defense is to tie you up in off-shore call centers but persist by asking for the call to be "escalated" until you get to a decision-maker.