Why did I receive an amount that doesn't match my calculations?

The returns that investors receive have already been deducted by the investor fee and are subject to legal tax deductions, including Value Added Tax (VAT 7%) and Withholding Tax (WHT 15%). 

Additionally, there are 2 types of bond repayment structures: amortizing repayment, where the principal is gradually repaid over time, and bullet repayment, where the entire principal is repaid at maturity. The repayment of principal and interest will differ depending on the structure.