Dear Budi,
I happen to have 1299 cc Uno mk1 too. I have been using it for 14 years.. ;-).
Firstly, try to change gear box oil as Dave suggest. Secondly check rubber bushing in transmission link, it might be broken. Lastly if you enggage 1st gear with a noisy sound come from transmission you might have to change shyncromesh gear.
Salam hangat,
Hendro. N