Deleted messages aren’t freeing up iCloud space

My iCloud storage filled up and is reporting 4.9gb of messages. I deleted hundreds of conversations containing thousands of messages full of photos from my iPhone. My iPhone storage now says messages is using 508mb, but iCloud continues to report 4.9gb used for messages and nags me repeatedly to upgrade. It’s been over a week, how do I get all of those old messages off iCloud? Yes, iCloud message sync is turned on, on my iPhone. Thank you.