hi im back. as i mentioned in my previous post, i buy my kimchi from a local korean market. super delicious, couldn’t ask for better. i usually buy 1.5kg of kimchi and it takes me a bit of time to get through it. when i get 1/4 left of it it starts getting sour and not the taste i’m most fond of. it’s still good don’t get me wrong, but it’s very gasified. what can i do to prevent this from happening?? i’d like for the taste to stay as it was when i first opened it lol. im not very familiar with fermentation so what im asking for is probably impossible what would i know

I made kimchi. I think it is about 2 months old.

This was my first time making Kimchi.
It showed bubbling for the first two days. Now it stopped bubbling. The kimchi is not sour enough (i gave a taste test)
The jar of kimchi is kept in a warm and dark spot.

What can i do
No moulds so far. Enough liquid present in the jar.
Taste is appropriately salty but not sour enough.
I open the jar once a day to burp, but able to feel the gases escaping like it used to in the first two days.
No bubbles on pressing the cabbage down.

Kindly help

Edit- adding the recipe

Vegetables used
Green cabbage
Green onions
Chayote cubes

Kimchi paste ingredients
Fermented fish
Chilli flakes
Onion
Garlic
Ginger
Soy sauce
Sugar
Cooked Rice paste

Salted the vegetables
Threw away the liquid brine
Gave a quick wash

Added the paste and mixed well
Added to the jar and kept in a cool dark place for fermentation