Got mine from Vaperstuff in FB. Postage available within Malaysia.
No kidding, I have a strawberry flavoured lube with the exact bottle, but in blue. Unrelated, yes. Just wanted to share my purchase history

Now I could be wrong, but what you have there is pure  uncut nicotine which should be handled with care. You could dilute by adding PG yourself in 10% dilution, but why bother. Just grab a ready PG based Nic from Vaperstuff and you're good to go. Plus a purchase of 100 min gets free shipping. That's like a bottle of 100mg nic worth.

Just like quite a lot of our local backyard brewers - the labels says 6 mg but in reality they only use 2 to 4 mg.

Not saying that your supplier is cheating you, but there are some un-scrupulous guys who dilute their nic by more than 25 percent lower.  If you are a serious home brewer, you should test the nic you bought to make sure the labeling is correct.  Google for diy nic strength test kit.

It could also be you made a mistake while keying in your ingredients into the online eliquid calculator.  You may consider cross checking by using manual calculation as follows:

Objective : to brew 30 ml juice with 6 mg nic using 48 mg strength nic base

amount of nicotine required will be 30 x 6 = 180 mg of nic

amount of nic base at 48 mg strength = 180/48 = 3.75 ml of nic base

By substituting the parameters, you can ensure that there are no mistakes made in your recipe.
But wait!!!   

Did you mix all ingredients thoroughly?
Did you steep the brew?  I don't think you did - you just test vape it immediately after mixing....

The lack of steeping may account for the lack of throat hit as the ingredients had not been steep properly.

OK the numbers make more sense after u edited the post.
Are u and the seller very sure it is 12mg strength nicotine? If you're absolutely certain, then 6mg target strength isn't for u; try 3mg.

It takes time to steep, depending on the ingredients. Could be a week, could be 3 weeks. Till then, it'll taste very rough.

Looks like uneven nic on your juice. Recommended steeping for nic is at least 2 days. Remember to shake it hard at least once a day.

12mg nic on vaping wont kill you, just harsh for some people.

Shake it and let it steep. Don't play around with nic. Liquid form nic is poison.

or an almost spoiled batch :c

I have never done business with vaper stuff although I did consider to purchase stuff from them. One reason is because they don't do business on weekends, and only do cod on weekdays.
I just checked again on their fb page that says there closed now. Opens Monday. So that's why (maybe?) the didn't respond to you.

A friend of mine looking to buy Wismec Releux DNA200. Any idea where to get? Shopee one fella selling 880. Hoping to get cheaper if got. Any local or reputable online seller?