Wanna share my experience on this matter. Hope this post can help anyone who might face it in the future.

I received a SMS from those 5 digit number notifying me about subscribed something, saying if want to stop, need to reply "STOP".
At first I thought it is just some scam SMS, so I never care about it.

Until one day I made a phone call, checked my balance then I noticed my credit were deducted so much since I last checked. This was around September.
At time I didn't relate or link it to the SMS that I've received previously. I thought maybe I made some called or what that cost me a lot, so I let it go and never further check on it.

A month has passed, one day I checked my balance again, found out my credit were deducted again. Now I know something is not right, so I checked my balance every day, notice my credit get deduct for RM1 each day.
I didn't subscribe to any internet data plan or anything, basically the number are idle most of the time.
Then I received a SMS from those 5 digit number again, saying the thing that I've subscribe has been renewed. Now I know it might be this thing.
So I replied "STOP" to stop it. But it didn't stop deducting my credit. Instead, a new 5 digit number sent me similar SMS saying I've subscribed to something.

At this point, it is ridiculous, I've at least received these kind of SMS from three to four 5 digit number.
So contacted the support staff via Maxis live chat. Told me that I might have clicked something from some ads or links which granted some third party to charge me. But again, my number are mostly idle. I'm sure I didn't click on anything nor consent anything.
I asked the staff to help me stop all of it, and maybe block them of charing me.

Few days later, the deduction are still happening. I contacted the support staff via maxis live chat again, this time around, they said it will takes about 1 week for the third party reply them and process everything, including refund.
Now only then they revealed is MacroKiosk. Which I googled and found this thread.
Okay, so now I wait. From time to time, I received SMS on topup credit, a few ringgit topup from every single SMS, but not full amount. The amount that I've lost on this case is around Rm100+.

At the moment of posting this post, credit deduction has stopped for two days. However refund of RM83 which mentioned by the support staff still not yet receive.
After I received the refund will update here again.

For the record, the support staff are always being helpful, really appreciate their patient and helps to settle the issue with me.
I've export the live chat transcripts to my email as well as proof. Recommend everyone to export the transcript and keep it as proof.
This could happen to anyone, please be aware and cautious when you notice credit were gone for no reason.

Yesterday received full refund amount. Credit deduction so far has stopped.

Yup. Very likely..