Faulty Flashing Digital fuel gauge, Fuel light always on, 1.4 tdci 2002

[Razzz]

Hi guys, new to the forum.

I need help with my Fiesta 1.4 TDCI 2002, which I've just bought.

This is the only problem the car had and the previous owner did mention this to me.

The Digital fuel indicator keeps flashing (all the bars, like its full) on and off and the fuel light constantly stays on.

I filled it up with as much diesel it could take and then some, thinking this would solve the problem but it hasn't

Please, any advise or help would be greatly appreciated

P.s there are no other problems with it, the fuel gets to the engine fine & the car runs perfectly

Thanks in advance

[Razzz]

Please guys any help/advice would be greataly appreciated.