What is your pay? If you got your card this year, applying to increase CL the chances of getting are very very high.
Either you use FD or wait till next year if you got salary increased.

Let's tackle the issue one step at a time.
Have you tried a gradual increase instead? Maybe request for a few thousand first as opposed to jacking it up to 3x your MBB2 credit limit?

For your info, I have also been using the MBB2 card since its launch, and have been using it for more than 3 years. I'm also pretty much like you, making full payment each and every month for the past 3 years. Credit limit is also a few times that of my salary. Expenditure is really heavy too as I use it for my business, in purchasing IT hardware. When I have projects, credit call statement exceeds RM20k per month.

Only missed the RM50 monthly cash back 2-3 times since I got the card. Treatpoints just crossed the 900k mark. I am taking huge money from them and they don't seem to have a problem with that, continuously increasing my credit limit every 6 months when I write in.

I suspect it could be because you have a high DSR (debt-service ratio)? Try to request in stages first as opposed to a lump sum as mentioned earlier on.

Different banks have different methodology and mathematical formulas in accessing customers's financial health. Some bank use the gross income, some use nett income. Some acknowledge 100% of a rental income, some apply a 20% discount to it while some don't even recognize such income unless its a proper stamped agreement. Same goes for the DSR, it varies significantly for clients in different income bracket and their CCRIS history.

AFAIK, MBB is quite strict on CL increase. I have other banks CC which gives me 2-3x my MBB CL.
Not sure if someone mention before, but you may submit your 3x latest salary slip and fill up form at counter to request increase CL.
I did that before and still, it was a very minimum increase.