Group message photo automatically changes

When I text in a group message with no group photo, everyone in the group gets a message that I changed the group picture, and even though I have not done anything to make that change! Suddenly, my profile pic is automatically assigned as the group message photo. I have checked all the settings. I have turned off the share profile photo setting. I have rebooted both the Messages app as well as my phone multiple times. The problem persists. Please help!