Instruct: Classify the given Amazon review as either positive or negative.
Query: Not happy with ours

We have two for our twins. The 5-point harness is much too hard to use. The lower straps are clearly not meant to be buckled and unbuckled every time, because they're much too cumbersome. We just slide the baby in instead, and attach the upper straps, which are also a real struggle to undo. The footrest doesn't stay down. Our babies like the vibration but the battery doesn't last real long, and it sometimes vibrates loose and we have to shake the footrest to get it going again.