I started to draw new polygons in a layer within an existing Geopackage that I previously created.

However, after editing, I sometimes (it seems a random phenomena) cannot save the layer and I get the error:

Errors: ERROR: feature(s) not added.

Provider errors: OGR error creating feature: failed to execute insert : database is locked

The polygons drawn are then lost, which is pretty frustrating.

I googled a lot and found this rather old fix. However, I’m not sure whether it solves the issue nor how to implement it.

Any suggestion? =) I'm using the latest version of QGIS (3.12).