This is exactly what i did as well and fixed mine immediately! I wish I had seen FionaC13's post earlier:

FionaC13
User level:
Level 1
(4 points)
Oct 9, 2019 12:39 AM in response to Aliestrema
I fixed mine... tried all the other suggestions and none of them corrected the issue except THIS ONE
Here’s what I did.....
1) went to Apple ID signed in to access icloud
2) went to iMessage toggle and turned off
3)this prompts iMessage to disable and Download
4) when this prompts press download and disable messages as per picture below
5) attach your iphone to your charger and access wifi if not already
6) your images will start to download and you will start to see each contact iMessage add the images, attachments etc that’s where previous to the update you could just hit info beside the contact and all the images were there, they will appear again...
7) be sure to turn the iMessage toggle back on after disabling it, you don’t have to wait. Do this right away...
8) can’t believe Apple couldn’t have posted this LOL
good luck!!