If user run the voucher posting process and voucher is not getting picked for posting then execute the below update statement and run the posting process.
select count(*) from ps_voucher where voucher_id in ('00033333','00033308') and business_unit='220001' and IN_PROCESS_FLG='Y'
(2 ROWS SELECTED)
update ps_voucher set IN_PROCESS_FLG='N' where voucher_id in ('00033333','00033308')and business_unit='220001' and IN_PROCESS_FLG='Y'
(2 ROWS UPDATED)