Issue with Reply-to Functionality in Website Contact Form Emails

Question

I've set up my website's SMTP to use Outlook/Microsoft Azure for sending contact form submissions. Until recently, the form submissions were correctly using the submitter's email as the reply-to address. This allowed me to simply hit "reply" to respond directly to the person who filled out the form.

However, in the past few days, this functionality has stopped working. Now, the reply-to address defaults to my own Outlook email instead of the submitter's email.

It has worked correctly for the past year.

I've tested this issue across three different websites with three different Outlook accounts, and it only occurs when using Outlook as the SMTP service.

Anyone with a similar issue or possible solution for this?