HDFC Home Loan Conversion enquiry and spread change

Hi, I have ongoing home loan with hdfc and it has spread of 2% so my current interest rate is 8.5 and from march it will be 8.25 but i want to ask if this spread is good or i can reduce it with conversion enquiry? Currently when i trying to use conversion enquiry it is showing that this loan is not eligible for conversion enquiry using online process.

Have you ever done this conversion enquiry? And how much spreas you were able to reduce? Also what is the minimum spread we can get?