If you're getting an error related to an ID like the one above, the ID might belong to an app, a page or an event that is not connected with the ad account or it might not be valid anymore. First thing to do is to check the pages, events and apps to see if the ID is connected with your ad account.
For instance, if this is an app ID you're getting an error for, you can follow these steps:
Go to https://business.facebook.com/settings/apps as business admin.
If the new app is not there:
Click "+ Add" > "Add an App"
Enter new app's id
A notification will be sent to app's admin to approve access
If app is already there:
Select the new app
Click "Add People"
Add the ad account's e-mail you'd like to connect it with as app admin
After completing these steps, the app will come up in auto complete. You shouldn't just paste the id of an app to use it. You need to select the new app from the auto complete for all targetings and save. If you're still getting an error related to the ID and it belongs to an old app, it's best to check if it's still being used in the campaign and if so, remove it and add the new ID.
If you're unable to find the ID or it's not solved by connecting it with the account, you need to get in touch with the CS team to get support.