Battery dead after 3 months for A1398 mid-2014 MacBook Pro with Retina

Installed a new battery after purchasing from iFixit & followed installation diligently.

Worked well for approximately 3 months & one day while on charge watching a YouTube video the battery status in the menu bar suddenly showed an 'X' from a % value. Immediately checked coconutBattery to see what was wrong & to my surprise it showed the battery status as 'Unknown'.

This is not what I expected in terms of quality, I was hoping it would at least last for a year before starting to lose charge or capacity. Is there anything more I can do to test it out apart from re-checking the connector? What else could be an issue? or is the battery just a lemon that I received & needs replacing?

Thank you.