A cautionary tale:
I had a similar problem when I had a Citroen BX. The garage said that I'd need to have the clutch replaced and, since that involved removing the whole of the suspension, it would involve 8½ hours labour and therefore cost a small fortune. However it was a good car and I agreed to have the work done.
A few days after the new clutch had been fitted however, I encountered further problems getting the car into gear. The garage made an adjustment and said that everything should be OK.
A few days later I was back at the garage with the same problem again. They eventually diagnosed the problem as a small L-shaped connector at the end of the clutch cable that had started to split (so that the two arms were no longer at 90 degrees to each other). They hammered it back into shape and welded it together, thus fixing the problem.
It was only when I was driving away from the garage that I realised I'd forked out hundreds of pounds to have a (totally unnecessary) new clutch fitted when all that been needed was a 5-minute job with a hammer and a welding torch! (That was the last time that I ever used that garage!).
So, please, please, please don't let anyone try to tell you that you need a new clutch until they've checked:
(a) the cable ; and
(b) the fittings at the end of it.
My guess is that your clutch cable has simply stretched and that fitting a new one (cheap part, minimal labour) will solve the problem.