Recently my toilet always overflow. I suspected it was due to the water inlet kept pumping in water.
My methods to Verify the Water Overflow
1. I adjust the water inlet lower.
2. If #1 fail, check whether there was water coming out from the water inlet hose

Adjust the Water Inlet
My water inlet can adjust its float. So I thought at first due to long time the float move by itself. So I lowered down the float.
Outcome: Still overflow
Check Whether Water Coming in from Water Inlet Hose
So I put the water inlet hose near the toilet body overnight. If it was wet then I know the water inlet needs to be replaced.

Outcome: Still overflow but the hose was dried.
Conclusion
For me there was only one conclusion because which was the water inlet that caused the water overflow. The water inlet was the only part that allows water to come in.
My Solution – Replace to new Water Inlet
At first I wanted to buy from Shopee which cost only around RM10, but after reading bad review. I decided to buy from a shop that cost me RM22. The quality is good and still works till now. I wanted to buy Techplas but it costs RM33 and at that time, I wasn’t really sure whether the overflow was really due to water inlet or other problems.
Outcome: No more overflow


Notes
I noticed after 8 years I have to change my toilet water inlet. I started to use the toilet in 2013. Now both my toilet water inlets have been replaced to new ones.