Basically if it has catkins then it is not blueberry.
Go and play hell with the garden centre that sold it to you.
(even better if you still have the label as proof of purchase)
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I would guess what happened is that the blueberry died, but a self-seeded Salix caprea or cinerea grew - this might have happened in the nursery (in which case supplier is definitely to blame) or afterwards - in which it depends on whether it was vigour of plant or suitability of cultivation that was the problem.

If the catkins are as in the google pictures, then they look to be female - it's the male tree that has the golden pollen-encrusted pussies.