Hi,
According to the module page :
- Dolibarr min version: 7.0.1
- Dolibarr max version: 9.0.*
- Prestashop min version: 1.6.0
- Prestashop max version: 1.7.*
So it is not supposed to work on V12. It is V9 max.
But you can try to download the latest version from Git : https://github.com/johanbernard/prestashop_to_dolibarr