Desktop sync client disconnected and bad performance

Hi,

I installed a Nextcloud installations this week (officical Nextcloud docker) and i having very bad preformance. After setting everything up, i downloaded the Desktop sync client and started to sync my data. After selecting the folder it needs to sync (not empty) it start to “index” everything and then just crashes. All the time… Even after a clean folder and then copying my data in, it just stops working…

Im using Windows 11, what else is needed to throubleshoot this issue?
Without a stable sync client im afraid i cant be using Nextcloud…

Kind regrads,
Graxo