I have a large txt file with 10 million rows and 16 columns and I already have imported the table as a delimited text file in QGIS. In row 7 and row 8, the coordinates are stored (I also allocated x and y to these coordinates).

In QGIS, the attribute table is displayed in the right format and all information is in place. However, if I want to export the table as a point shapefile, it shows (and exports) only the headers, but with no content (no attributes).

Do you have any ideas, why this happens? I am using QGIS 3.16.