Ziyech, 29, arrived in Paris to complete the move, with both clubs on board after the former £35million signing struggled to force his way into Graham Potter's plans.
The Moroccan international has made only four starts this Premier League season to go with six brief substitute appearances, collecting his first goal involvement with an assist against Crystal Palace on 15 January.
According to The Athletic, Chelsea is the side being accused of failing to submit the necessary paperwork in time for the move to be processed, while an anonymous Paris Saint-Germain source is quoted calling the situation a "Class A circus".
ESPN adds that the French giant believes the paperwork was filed in time and will appeal the Ligue 1 decision, but there is no timetable for the appeal process.
