I have seen in various threads that there is concern regarding the loss of naturalised citizenship after a 3 year absence from Paraguay.
Article 150 of the National Constitution of Paraguay clearly establishes that a naturalised Paraguayan will lose their Paraguayan citizenship by unwarranted absence from Paraguay for 3 years.
In practice there is no procedure that causes this to happen automatically. To begin the proceedings an individual or institution, eg Migraciones, would have to initiate a judgement against the individual. A judge would have to declare the loss of citizenship and the procedure, which would need to be taken through the courts, could take a long time.
It is very rare for this to happen as most foreigners who seek residency either live here, are investors and generate income in Paraguay and often make job opportunities for Paraguayans.
The suggestion that I always make to my clients is that they return to Paraguay at least every 2 years and in this way problems with immigration administrative authorities are avoided.