Repeater inside a repeater

Hello,

I have to export elements from one site using the all export plugin and re-import them into another site where there is the same ACF structure

I have a repeater inside another repeater.

The parent repeater is called “activators”;
it has the following subfields:

• detail (type = text)
• polygon (type = repeater) subfields:
  • latitude (type = numeric)
  • longitude (type = numeric)

In All Import I set activators as Variable Repeater Mode (CSV) with Separator Character | and polygon as Variable Repeater Mode (CSV) with Separator Character ,

In the export I have:
“Da mappa|Da mappa”, “45.47,45.47,45.50|44.12,43.58,41,31”, “45.48,46.847|44.12,43.58”

When I import I get:
data”:{“status”:500,”error”:{“type”:1,”message”:”Uncaught TypeError:? explode(): Argument #2 ($string) must be of type string,

why? How should I do it?

Thanks