Following your advice I used the plugin “loco translate” to translate, however, I found that ( I don’t know for what reason ) the translations get lost. When I look in the plugin, the translations are not there. It has happened to me twice so I replaced it with another solution for now, but it can’t translate the texts in the search fields.
Please advise me how to solve this.
Most likely you had the wrong path with translations and after update, they were lost. We require that you select “Custom” for the location (through the “loco” subfolder), this is Loco’s protected folder which is safe from automatic updates and provides priority over other locations.