Categories won't save at first time - jQuery Conflict?

[demaluca]

Hi there
i've a problem with my site.

When i create a new product in the backend and assign categories, these won't save.
But if i refresh the page, they appears.

So i try to delete them and save. Nothing changes. But if i refresh the page, they've been removed.

So: how can i make this work properly, without REFRESH the page each time i want to edit something??

Thanks

VM Version: VirtueMart 3.2.14
Joomla 3.8.7

[Studio 42]

have you some error message in the javascript console(F12 to open it)