rewrite the text to be less complex:
Article 12 Revocation of authorisation If unforeseen occurrences adversely affecting the environment or native populations occur, the competent authority may provisionally or permanently withdraw the authorisation at any time.
Article 12 Withdrawal of permit At any point in time, the Competent Authority can withdraw the permit, temporarily or permanently, if unforeseen events with negative effects on the environment or on native populations occur.