New Battery or Something Else?

I have a 2017 petrol Octavio which I hadn't used for a couple of weeks and when I tried to start it the battery was flat.

I charged the battery for a few hours and locked the car without starting the engine as I was in a rush.

When I went back and tried to start the engine it wouldn't start and the alarm started going off. There were lots of warning lights on the dash and I couldn't stop the alarm using the key. I ended up having to disconnect the battery to stop the alarm.

I'm guessing there's probably a problem with the battery and that I'll have to replace it.

Do you guys agree or could it be something else?

The current battery is the Banner EFB 6R0 915 105 B which I guess is the original one. If I have to replace it, any recommendations for a reasonably priced alternative?

And will I have to get it "coded" or something before it will work? What does that involved please?

Thanks in advance!

Edited 1 hour ago1 hr by Archie_D
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