Product position in category not saved correctly

I have a strange problem in our Magento 2.4 installation.
In a product category you are able to specify the position of a given product by entering a value in the position column. This helps to display the products in the order you want. In our 2.4 updated installation entering or changing the numbers to whatever value you find suitable doesn’t work anymore. After saving the category Magento will have chosen another number and thereby ignoring or overwriting my choice.
Any ideas of how to solve this?