Why do credit providers not reduce interest rates in all cases?

As per the National Credit Act (NCA) credit providers do not have to reduce interest rates.

The good news is that many credit providers are willing to reduce interest rates so that a consumer can get out of debt in a reasonable period of time.

If the debt is to be settled in 60 months or under (for unsecured debts such as personal loans, store cards and credit cards) then most credit providers will accept the new payment plan. If the proposed new payment plan is over an excessive period of time, then many creditors will reject the proposal and there will be no reduction in interest rate.