QGIS caches the data for the layers it is showing. This can be a bit annoying when the data changes and QGIS doesn’t know about this. What is missing is some kind of “reload layer data” function. Instead I have to remove layers and add them again all the time. Or, instead of reloading each layer, I reload the whole project. Still, this needs several clicks and after the reload you are back to the project extent instead of where you were before the reload.