GSTR-4 UNREGISTERED PURCHASE

GSTR 4-ANNUAL RETURN

table- 4C - Inward supplies received from an unregistered supplier

i have purchased 3 lakh from a unregistered party(abc ltd) and 1 lkah from another (zyz ltd) 

in TABLE -C cannot save 2 parties purchase amount without ading PAN NUMBER

IS THERE PAN MANDATORY???