I'm following 1g protein per pound of bodyweight until recently and I got some gains. In your case, 55kg=121lbs so you will need 120+g of protein everyday.

I started a vegetarian diet recently which admittedly kinda hard to find protein sources so now I'm taking only 0.8g per per pound of bodyweight.

Oh no worries. I think everyone just need to take whatever amount of protein and adjust accordingly every few weeks or so based on their results. I try to reduce my intake mostly because I don't want to waste more money than I should lol.