I know I should have read the manual first, but didn't. I didn't charge it up fully before turning on, I pluged in for some minutes via computer usb, then turned it on, used for 1 minute, and put it back to charge. But the lights didn't turn on, so I changed outlet, tried it via pc usb, but lights never turned on again. It was weird but, since I just opened it, thought to troubleshoot it later, so I gave it a go and synced with phone.

Until was was left of the charge ran out, and I haven't been able to charge, pluged in different outlets, none of them seems to work.

I believe it has to do with activation. I have a second battery, tried it, it just never seems to charge. What do I do? Is it possible to re-activate the battery? Or reset activation?

Lozbo, sorry for the difficulties, it may not the activation issue, please double check the charging cable, try to turn it or pull out a little bit and charge via the USB port in computer.
If possible, I suggest to change another cable for troubleshooting.

I tried charging it in several places with different chargers, I don't have another cable.