PS4 controller lights up green when charging/trying to pair.

Hi there, new to the sub so apologies if I don't properly lay out the issues that I'm having but I'll try to give as much relevant info as I can.

So I have two Sony dualshock 4 controllers, the blue one is a CUH-ZCT2E & gold one a 409B-CUHZCT2A. I'll be referring to their colors from now on.

The Blue controller I tried swopping the sticks for hall affects. Everything went fairly well & took my time to not mess anything up.

After reassembly when I put it on charge the charging light came on & did the usual orange pulse, left it for a few minutes to charge then the vibration motors started going off randomly.

Unplugged & dissembled it again & removed the battery to stop the rumbling. Checked the board & didn't notice any missing or burnt components but there was still some flux that is missed. Cleaned the entire board with 99% isopropyl & reassembled.

After putting it back together again the controller didn't rumble anymore but the light now shows green when charging & flickers between green & a bit of orange when attempting to power on & doesn't connect to console anymore.

Used a spare controllers parts to test the charging flex cable & still has the green light issue so don't think it's the flex since the original flex worked normally on the spare as well.

Then my Gold controller: It charges & lights up normally but when I press the ps button to power on it flashes the white light once sometimes twice then completely stops. So it's unable the connect with the console since it doesn't stay on long enough.

However it enters pairing mode (ps+share button simultaneously) just fine & connects to my phone without any problems & even works.

No idea what the issue is since I've never opened it up before & was working fine when I had is connected to my ps3 but now can't reconnect it to the ps4.

Any insight on how to solve any of these issues would be greatly appreciated.

Ps: I've tried pressing & holding the reset button for about 10 seconds on both controllers to no avail.