New battery not charging - green light

Hello! I own a 13” Early 2011 MBP, which I love. I’ve upgrade to new RAM and an SSD over the years and it really serves me well.

So many years after its purchase in 2011, it was time for me to replace the original battery, as it wouldn’t last at all and after a point it wouldn’t charge either. That lead me to order a new replacement battery from iFixit.

After installing the new battery, I noticed that the light indicator was green and the battery wasn’t charging. I reset the SMC and tried again with no success. I thought that the charger might cause the issue, but then I figured I could run the MacBook without a battery installed. The laptop wouldn’t boot up with the drained battery installed. From that I got to the conclusion that the charger can deliver sufficient power.

I emailed iFixit thinking I received a defective battery and they sent me a new replacement. I’ve installed the 2nd new battery and the issue still persists. I reset the SMC again and powered on and off the laptop a couple of times. The battery is not charging.

During some very rare occasions, the light turns orange and the battery does charge. Furthermore, sometimes the laptop can power on without a battery, while other times the macbook’s sleep light indicator blinks 1 long and 3 short times and it does not power on.

The 2nd new battery:

The original one:

Logic board issue? Software issue? Am I just unlucky and all of the batteries are defective?

I would appreciate very much any suggestions/ideas.