Audi a6 c7

[fak]

Hi everyone. Just wanted to ask what could be causing the problem, I don't know if its cylinder or clutch or something else. The symptoms I've got is squeaking clutch when I press it, in the morning it bangs when I put it in reverse, after motorway run the gearbox won't go into any gears at first, the clutch pedal was stuck to the floor then popped by up by itself after a few seconds. And now in the morning it won't go into any gears but I keep trying then it works fine.  The gearbox changes gear perfectly with engine off, then I turn engine on an it struggles 2 get into gear. Thanks

[Magnet]

Hello Fakher,

Symptoms are not untypical of clutch release bearing failure. 
Kind regards,

Gareth.