Dualshock 4 odd power behavior

Hello there! So I've got a little bit of a special snowflake issue right here. I cannot google my way through cause everything points to "battery not charging".

Okay so, I bought a new aftermarket battery. I plugged it in. It seemed to work. The lights blinked, it was alright.

I then plugged it onto my PS4 to sync it. Again, it worked, charging icon was on. Then I turned off the controller from my PS4, unplugged the controller and... the controller did not react to PS button press anymore.

I plugged it in again, it synced, it worked.

I plugged it out while it was on... it stayed on. And it worked with my PS4!

.. Until I manually turned it off again through PS4.

Funny thing: It does not react to PS button when turned off, UNLESS I hit reset button on the back of the controller. THEN, it loses the syncs, and reacts and tries to sync (blinks again). As soon as I sync it (connect it to a PS4) though, the same thing happens again. Works until I turn the controller off manually.

TL;DR:

From what I've gathered, main point is - the controller WORKS when you reset it. It tries to find a PS4. The battery is actually full. BUT, as soon as I either sync it with a PS4 or connect it to a PC, and it "remembers" one machine, it then refuses to turn on, or even start blinking. By that I mean, it WORKS when it is connected, it EVEN WORKS when I disconnect it but keep it ON, but as soon as I turn the controller OFF, it refuses to start blinking. ONLY AFTER I RESET IT with the button on the back, the routine begins again. WORKS, tries to find a machine.