Gameboy Advance - doesn't turn ON (ON/OFF switch cleaned)

Hi guys!

I have this old GBA which doesn't work and I decided to try to repair it. There was battery leak inside and the power button was damaged. At first the gameboy didn't turn at all. I disassembled it, opened the power switch, cleaned it up and I now it's still not working (haha) but there is som led blinking for a while and just a milisecond buzzing sound from the speaker.

I have also tried to jump the switch ON pins with a wire to bypass the switch but the result was the same.

I have also checked continuity from + -> F1 -> 101 -> Q5

No screen at all...could you please help me what should I try next?