Hello sweett81,
It sounds like you are seeing some notification badges on the Messages app even though you don't have any unread messages, right?
Let's have you disable the Badge App Icon setting on your device, restart , and then enable the Badge App Icon setting once more. To do this, you can tap Settings > Notifications > Messages. Then, tap the option to disable the Badge App Icon setting, and restart:
Restart your iPhone, iPad, or iPod touch
"How to restart your iPhone X, 11, 12, 13, or later
- Press and hold either volume button and the side button until the power-off slider appears.
- Drag the slider, then wait 30 seconds for your device to turn off. If your device is frozen or unresponsive, force restart your device.
- To turn your device back on, press and hold the side button (on the right side of your iPhone) until you see the Apple logo."
After the iPhone restarts, go ahead and enable the Badge App Icon setting.
Regards.