Good day.
According to the current legislation of Ukraine, collectors have no right to sell your or any other apartment. If collectors have sold your apartment, you should contact the police immediately. It is also necessary to apply to the court with a claim to claim the apartment from someone else's illegal possession.
It should be noted that any debt enforcement measures can be used exclusively:
bodies of the executive service;
by a court decision that has entered into force;
subject to the submission of an executive letter and opening of executive proceedings;
in compliance with all official procedures provided for by the Law of Ukraine "On Executive Proceedings".
Collectors have no right to do any of the above.