How to remove redundant records of quota?

This is the operation:

  1. add 5 users( user01,user02,user03,user04,user05 ).
  2. set quota for them.
  3. write some data with these users.
  4. delete user02 and user04
  5. repquota -av
    *** Report for user quotas on device /dev/sdc
    Block grace time: 7days; Inode grace time: 7days
    Block limits File limits
    User used soft hard grace used soft hard grace

user01 – 1456 1024000 0 5 0 0
user03 – 1456 1024000 0 5 0 0
user04 – 1456 1024000 0 5 0 0
#501 – 1456 1024000 0 5 0 0
#503 – 1456 1024000 0 5 0 0

How to clean these records like #501 and #503 ?
Please help me. Many thanks.