Respected Sir,
As per section 44AA if income from business exceeds Rs.1,20,000/- and the total sales/turnover/gross receipts are in excess of Rs.10,00,000/- in all the three years immediately preceding previous year or in case the business is newly setup, income & sales/turnover/gross receipts are likely to exceed the said amount than the Assessee is required to maintain books of accounts.
Also the assessee opting for provision of section 44AD are not required to maintain books of accounts provided the conditions of section 44AD are satisfied.
However if the assesse does not opt for provisions of section 44AD than in such case he is not required to maintain books of accounts as per section 44AA (since income from PGBP is only Rs.90,000 i.e. less than Rs.1,20,000/-) and since sales/turnover/gross receipts does not exceed Rs.1 crore he is not covered under section 44AB of Income Tax Act, 1961.
Conclusion
Hence as per the provisions discussed above if the assesse does not opt for 44AD than section 44AA & 44AB are not applicable.
Section 44AD is not mandatory, it is optional to the assessee.
Hope i have resolved your problem.