Hello Vandana -
Sorry for late response.Actually the problem is your KNVH Table for customer 30000526 does not have HKUNNR entry.When you create sales order for higher level customer it looks for KNVH- HKUNNR to get Higher level hierarchy and that's the reason 1C did not get determined for customer 30000526.
solution - create one dummy customer in same sales area having same account group ...Let say 30000528 and assign it on top of 30000526.So your VDH1n Should be like as follows -
30000528
30000526
30000527.
Now create sales order and check your partner function tab should Hierarchy partner function 1C as 30000528 and check your pricing.I am sure you will get your pricing .
Please let me know if you face any issue or share your challanges to resolve it.
Thanks
Amit Gupta