Hi Shrivas,
It is not possible to create the customer without account group with the number ranges.
However in your program:
1. What kind of fields you need to insert in KNA1 table
2. You only prepare the internal table for required fields, don't use the whole KNA1 table.
3. your insert statement is wrong, check the syntax.
4. if you want to create the customer, find the BAPI or any FM
finally what is your business requirement?
Rg, Kiran