My car keep having problem with the fuel level meter, still reads low or no fuel even after refueling to full tank...

Back in May, I already had both the fuel level sensor and fuel sender changed. But about a month ago, the problem came back again. I first had the fuel level sensor replaced (it was found broken and started to fall apart), it worked fine but problem came back after only one full tank of fuel. Then the fuel sender was replaced as well.... all seemed to work fine... until tonight, the fuel level was wrong again:

I had about 1/8 tank left (orange light was not lid yet), decided to drop in the fuel station to refuel to full tank. After start up, the fuel level meter remain as before (1/8 tank) instead of showing full tank. Base on the last experience, the fuel level will just keep dropping as I drive, until the orange light comes... then it just stuck there even though the are still a lot of fuel.

1) Has anyone had such problem before?
2) What else could this be besides the sensor and sender?
3) Would putting too much fuel in the tank cause damages to the sensors?
4) Anything to do with using 95 (instead of 98) octane fuel?

ANY advice would be greatly appreciated.

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