Hi Guys... need some advice here.
I recently changed my internet from Maxis Astro bundle to a standalone one because my parents decided to cancel Astro.
I applied for the Maxis home fibre, they sent some technician to install with a new router.
It's been a month, and I felt that the connection gets disconnected intermittently - because I am still working from home I can tell that my internet disconnected as my VPN will have a pop up that it is disconnected and reconnecting.
I called Maxis, they sent someone over.
The technician said there is nothing wrong with my internet, but my disconnection issue is probably my room is not near the router.
He explained that I never experience in the past as now we have 5g signal, so there could be interference as there are 2 signals being transmitted (2.4g and 5g)
He suggested me to get wifi booster to get a better signal.
I did some reading on wifi extender, mesh network, and also get to know that routers may also affect the connection.
So I would like to ask if anyone had similar issue, and what would be the best solution?
TL/DR version:
I experience intermittent disconnection using Maxis home fiber plan.
I stay double story, router installed in living room. My room is on 1st floor far behind.
Maxis technician suggest wifi extender - wanna ask if you had similar issue and your suggested solution.
There are only my parents and I at home, I don't really need very canggih solutions as they are not very tech-savy. I just need to work with smooth internet in my room.
In case you suggest me to work closer to the router, my job requires some privacy and my router is installed near the TV.
Any comments is very much appreciated.

Replace the original router with better one. Also if double story have to look at mesh solution to ensure stable wifi across both floors. Can consider the TP-Link Deco M4 or M9 depending on budget. If you don't know how to setup then just get the tech person from shop to do it.
I'm only taking the 30mbps. Can consider to upgrade - but the technician said nothing wrong with the speed, it's the signal.
Maxis have me Archer Cv5.
what's VOIP?
It's the Maxis phoneline. If you're not using then you can completely put aside the default router.