New Viax 300 not mowing / spinning blades

I just installed a Viax 300 and set in the map. The home base is on a pavement, the mow area is 2 meters away. I set up a path as the installation suggested and the 300 moves to and from the starting piont and charge base.  When it stats mowing, it doesn't seem to mow; I can set the height from 60 to 20, but it doesn't seem to mow when it crosses the grass. I see no bits of cut grass on the underside of the mower. I've put it on/off a few times, and let it start again, every time neatly going to the starting point on the grass, but when it then moves, it doesn't seem to mow. Firmware was updated: 4.3.6_0398

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Well would you say. Just after I posted this, I decided to have one final go at it. Turned the 300 off, on, told it to go. It went to the starting postition, and started to mow!  I don't know what I have done differently than the other times.

Hello. Did you encounter this issue after updating to the new version? We suggest you try clearing the application cache on your phone and then restarting it. This should restore normal functionality. If the problem persists, please contact our after-sales support. Since we understand you are located in the Netherlands, here is the after-sales contact information for the Netherlands:

Email: aftersales@mova-tech.com

Phone: +31 020 8967747

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