Steps reverting back

Hi. I hope someone could help me.

I have just upgraded from a Vivosmart 4 to a 5.

I tested it out by doing a couple of walks and everything seemed to record perfectly to the Connect App.

I therefore totally disconnected my Vivosmart 4, rebooted my phone and the 5. However the 5 is recording my steps and it's reflected on the Connect App but when it does and automatic or I trigger a manual sync the steps on both my phone and the 5 revert back to a previous number. 

My phone is Android.... Motorola G22.

Any import/observations are gratefully received.

Thanks.