Hi @johnnymongiat,
If i give time step as hours or days by converting to milliseconds, it was not validating properly(For example if i generate otp at today 8 Am and it was expiring at day after tomorrow 5:30 AM (GMT time)) and also it takes the time zone calculation as well. Request you to update the code in this issue. I have used HMACSHA512 algorithm with 6 digits. Tried with 30 days but its validating less than 30 days only.