In the command button, I have the following coding

IF !EMPTY(ThisForm.txtRecDate.Value) AND !EMPTY(ThisForm.txtVendorinvoicenumber.Value) AND thisform.checkduedate()
	ThisForm.oAP.PostPtAccrual(v_apinvoice1.Apinvoiceid,v_apinvoice1.invRecDate)
	thisform.Release()
ELSE
	ThisForm.oAP.PostAPInvoice_(v_apinvoice1.Apinvoiceid,v_apinvoice1.sessiondate)
	thisform.txtduedate.setfocus
ENDIF

thisform has defined a property oAP that is setted with .NULL. value
postptaccural() function is present in cap.prg program.

when executing the line

ThisForm.oAP.PostPtAccrual(v_apinvoice1.Apinvoiceid,v_apinvoice1.invRecDate)

I am getting error as "Property PostPtAccural is not found"

Please help me to correct this error.