Mac charger blinking light from green to orange HELP!!! URGENT!!!

I have a MacBook from 2007 so please bare in mind that, yes, it is pretty old. My charger earlier in the week started flickering it's light, before I just unplugged it then plugged it back in and it was fixed. Now it won't charge my computer at all. I've tried everything! I have reset the SMC, I've taken the battery out and put it back in, Ive taken it apart and i am restless at this point. I know it's the not charger but something from the inside my computer but I don't know what. it actually started to work when I cleaned out the port when the charger magnetically gets put in and then thought, "oh the magnetic flow was just blocked because it was dirty". That worked for maybe an hour and a half. Then my computer turned off, I guess I hadn't noticed it was flickering again Causing it to die. This morning I plugged it back in it worked for a minute then turned off. Please can anyone help me please