esp32 E.openFile stops working after multiple fs.readFile and fs.writeFile

The open/write/close pattern comment was made upon @Wilberforce's post #4.

Accessing a property of an object with property name as string or string variable in square bracket provides the ability to do it dynamic. No different ends, just different means (internally it goes a little bit a different path).

In deed, nothing what so ever tried helps... Ic.