Samsung galaxy S10+ battery life

[Scottlowe88]

Just got a Samsung S10+ which was described as "like new" from O2. Firstly it just came in a cardboard sleeve with no plug, no headphones and not much protection. I had to buy a genuine samsung charger anyway because the fast charging feature wouldn't work with any of the plugs I already had.
After using the phone for a few days I realised the battery is terrible on this phone. I read some reviews stating they get 12 hours from one charge.
I fully charged overnight last night, got up at 7am and used my phone as normal. By 10ish I was already on 50 percent!! Done the usual checks with apps running in background etc. The power settings are at optimal.
I wondered if batteries are checked before being sent to customers? Could it be the battery is past it's best due to charging etc. Or is it just this phone has bad battery consumption?
Any help on this would be appreciated.
Thanks

[MI5]

@Scottlowe88 

Send it back for a replacement.

It should do better than that Guide: Coronavirus Community Help and Support 

[Scottlowe88]

Might sound daft but do I need to phone them to sort that? Will it be straight forward with it being Easter and lockdown?
Thanks

[MI5]

Nothing straight forward right now but you have no choice.