We had our application running till Friday 10/14 without an issue from last 6 months. It uses Single Send API to send email to a contact.
Since 10/14, we have noticed that some emails sent through it are not merging custom properties submitted to API. I have debugged and all values are getting submitted properly to API. This is also not a consistent behavior. I created multiple email templates to play with it and noticed that as soon as I add a decimal value, some custom properties stop working. This was not the case before 10/14. We have not made any code changes and it have sent more 100,000 emails with it before.
Any help is appreciated.