The story
In early 2014, the airline received the first of two Sukhoi Superjet 100 aircraft, which was due to be operated under a lease agreement for AtlasJet on charter flights. The airline was the official carrier of the volleyball club VC Lokomotiv-Belogorie.
On 17 September 2015, Rosaviation announced the suspension of Centre-South Airlines' operating certificate due to several violations. Following the rules, if the airline plans to have a wide range of flights (as Center-South has), it needs to have not less than 8 aircraft with capacity of not less than 50 people, however, the airline has only five aircraft of the required type, including two Tupolev Tu-134 and three Sukhoi Superjet 100. The aircraft had also never been checked for damages.
From Wikipedia’s article on Center-South, shared under CC BY-SA 4.0.3