Hello ~ Take a look here by clicking on these….
Delete and recover messages on your iPhone or iPad*
*Retrieve a deleted message or conversation
- In Messages, tap Edit.
- Tap Show Recently Deleted .
- Choose the conversations with the messages you want to restore, then tap Recover.
- Tap Recover Message or Recover [Number] Messages.
You need iOS 16, iPadOS 16.1, or later to recover deleted messages and conversations. You can only recover messages and conversations that you deleted within the last 30 to 40 days.
Have you deleted any messages since you updated?
~Katana-San~