I had quite a similar problem with my 1998 Punto. My clutch slave was leaking, so replaced that.
So I told my bro in-law my problem. He told me to check the clutch arm as it goes inside the bell housing. He said ' most people ( mechanics) never bother greasing the arm as it comes out quite easy'. So cover the fork arm in WD wait a day or two, then pour some oil of any grade down it'.
Also told me to attach a pair of mole grips and give the arm that the slave pushes it, a hand,.
But it never needed any assistance. It freed, used up my squeaky oil can to oil it anyhow. But, before it got so bad it jammed the clutch on. So no gears could be selected at all.