Peeps around the world has to overcome the previous loans and increased interest rate is not only applicable to new applications but also to the existing loans.
That only happens in variable interest mortgages as far as I know. Or the mixed ones, which have a variable part. I don't know how it will be in India but in the rest of the loans, such as personal loans, they are usually at a fixed interest rate and it doesn't matter how much the rates go up or down once the loan is signed. You are charged the interest rate of the contract you have signed without variation.