Sounds like you are correct that this is not correct and when it doesn't go into a gear, normally first or reverse, the issue is the clutch is not fully disengaging.
There are a number of possible causes but I suspect the slave cylinder has air in it or is leaking now.
Here are a couple guides that will help with this:
https://www.2carpros.com/articles/clutch-doesnt-work-sometimes-or-not-at-all
https://www.2carpros.com/articles/throw-out-bearing-replacement
Clearly they may need to drive it in order to see that it is not right so you may have to take it back.
However, I am attaching the info from the manual on the slave cylinder as I suspect this is the issue or at the least it needs to be bled.
Please run through this info and let us know what you find.
Thanks
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Friday, August 6th, 2021 AT 7:29 PM