Change Record feild for APP_FOLDER.TRX_NUMBER AR receipt form

Hi

I need help in AR receipt form  fro record group change for APP_FOLDER.TRX_NUMBER .

please check below query

select /*+FIRST_ROWS */

ot.trx_number ,

ot.customer_id ,

ot.customer_number ,

ot.class ,

SUBSTRB(ot.class_meaning, 1, 30) class_meaning ,

ot.trx_type ,

ot.cust_trx_type_id ,

ot.trx_due_date trx_due_date ,

SUBSTRB(decode(sign(ot.payment_schedule_id),-1, :app_main.currency_code,

              ot.invoice_currency_code), 1, 15) invoice_currency_code ,

ot.balance_due_curr ,

decode(sign(ot.payment_schedule_id),-1, to_number(null),

              ot.balance_due_functional) balance_due_functional,

ot.customer_name ,

ot.location,