Skoda Scala 1.0 TSI 2023 - Stiff Gear Change

Hi everyone. My son bought a 2023 Skoda Scala 1.0 TST Monte Carlo back in April. It's a beautifiul car. Early in the summer (on one of the days it was 35C) he said that it wouldn't go into gear after having it parked all day, although after a bit of trying it was fine. This didn't happen again until last month when the same issue occured. Over the last few weeks he says it's been happening more often, although it is still only intermittent. As there was no record of the car having it's brake fluid changed at 3 years he had this done at our local garage yesterday, along with the clutch fluid as we know it's shared. The garage said the fluid was low, and now that's all done. He was hopeful that that was the problem sorted but it happened again this afternoon.

This time I was able to get into the car and feel it for myself. The gear change felt stiff and required more of a push than usual to get it into gear. Lifting and then reengaging the clutch resolves the issue.

A quick search on the web suggests lubricating the linkages in the engine bay with lithium grease - that looks easily doable and worth a go, but I'd appreciate any other thoughts or suggestions.

Car has 23,000 miles, full service history - and is no longer under warranty from the garage we bought it from (of course!)

Thanks in advance for any advice.