If you have already tested positive, you do not need to have another test before you end your isolation period.
After having COVI9-19, the risk of re‑infection is extremely low in the first month and remains low for 3 months following COVID-19.
Test using a RAT (not a PCR) if there are new symptoms of COVID‑19 up to 3 months following COVID-19 infection. PCR tests have a high false positive rate in the months after infection, due to detection of persisting viral fragments. A positive RAT can be taken to indicate re‑infection.
At 3 months after COVID-19 recovery, revert to usual testing practice.