Looks like you have not given value for the second attribute "cr_number" after "where" clause
.CommandText = "update cr_record " & _
"set cr_record.isu=@isu," & _
"cr_record.Nama=@Nama," & _
"cr_record.pnum=@pnum," & _
"cr_record.date1=@date1," & _
"cr_record.DeptDesc=@DeptDesc," & _
"cr_record.email=@email," & _
"cr_record.change1=@change1," & _
"cr_record.reasonchange=@reasonchange," & _
"cr_record.problem=@problem," & _
"cr_record.priority=@priority," & _
"cr_record.reasondescription=@reasondescription," & _
"cr_record.systemrequest=@systemrequest " & _
"where cr_record.Emplid=@Emplid and cr_number=@cr_number"