As the related url shows all bar charts show only first item at the moment:

https://studentvoice.today/voorbeeld-resultaten/ 

I see an error in the charts wizard: Cannot read properties of undefined (reading lenth) See attachment. 

Is this a known issue? Is there a temporary solution? 

Thanks for your attention.

we have the same problem. are you using google charts?

Yes, using google charts in wp-data-tables

Solved! Problem was solved today. Without any updates. Remarkable.