Clutch pedal hard?

Based on your description it sounds like the pressure plate is not releasing the disc. This can only happen if the springs on the plate are failing or the release for is not being pushed down to an intermittent problem in the hydraulic system .When the hydraulics fail even intermittent it would be felt in the pedal.If hydraulics checked ok then  it sounds more clutch place/disc related.

Get the hydraulics ie the master and slave cylinders inspected as soon as you can. The clutch plate and disc at difficult to inspect.

A professional car mechanic or inspection at dealer ship is required.

This will help.

Thanks.

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