Clutch issues??

So recently purchased a fiesta st line black edition 2017 in January 2023
And from day dot had an issue with the clutch
When the vehicle has sat for a period of time when starting the vehicle and putting it into reverse or first the biting point of the clutch is right on the carpet and the car won’t come out of gear so have to turn the car off and start again with this the bite point is just off the carpet and there is slack from the pedal on release, once the car drives the gears and clutch are absolutely fine this seems to be a very intermittent problem and had the vehicle into a main dealer when they said they can’t find a fault and then a couple days later the problem reoccurs any ideas of what this could be there is no leaking in the footwell or the underneath it also seems to occur when using the clutch in traffic ???

Slave cylinder probably died (Seals).

Changing the fluid (Brake resevior siphons off the master cylinder/brake circuit) could help iif you've got too much water in the fluid.

I had this for 2 months, I replaced the master clutch master was an annoying job, bled it again. Fixed it for a day everytime I bled the system. My thrust bearing on my actual release went after I dropped the gearbox and done a clutch and flywheel with my release bearing. Start off east and get a brake fluid change done and bleed the release. Should have a yellow cap at the front of the engine slightly over to the passenger side. Do all your brakes it might fix it for good but if not definitely do the master next as it’s easier than dropping the gearbox. It’s also very cheap from euros or GSF car parts. I did both and then still had an issue so dropped the gearbox and just put a new flywheel and st200 clutch and diaphragm in with new release bearing. It’s not bad of a job took like 2.5-3hours to do but I am also a technician and have a ramp. If uncertain just drop a reply and I’m happy to help out