As per Sec 44 read with rule 80 :-
Every registered person whose aggregate turnover exceeds Rs 2 crore is required to file:
 - Annual Return GSTR 9
 - Reconciliation Statement GSTR 9C (if turnover exceeds Rs 5 crore)
 - Audited financial Statement 
before 31st Dec 2023

Consequencies for not filing GSTR 9
 - late fees Rs 100/ day (Max 0.02% of turnover)

Notes: 
 - In case of Multiple GSTIN 
   ( if any GSTIN has nil turnover than also GSTR 9 is mandatory)
 - GSTR 9 can't be revised
 - GSTR 9 can be filed upto 3 years from due date of financial year
 - Opportunity for assessee to correct his mistakes in GSTR 1 & GSTR 3B filed during the year.
 - if excess ITC claimed incorrectly then gst can be paid using DRC-03
   
     Thanks & regards  
 tarun.lamba09@gmail.com