Here are the main reasons why campaign replication may fail:
Hover over the red cross to know what is the issue.
Errors due to In-App Themes
In case of replicating a campaign with a specific theme for the In-App or mobile landing attached to the push, you need to first replicate the theme.
Select the application where the campaign will be replicated. Go to Settings > Theme > Themes from other app. Select the one you want to add to the collection and click to Attach.
Error due to Language:
Default Language is not the same on the two apps: Go to Settings > General > Default language.
Error due to Labels:
Make sure the labels used in your campaign are created on all the apps with the same code. To manage (or create) a label: Go to Settings > Labels > Edit an existing label or Create new label.
Error due to Targeting:
Make sure the Custom Data targeted are enabled on the app where you want to replicate the campaign. Go to Settings > Custom Data on both apps or websites and compare. If you enable a Custom Data, don't forget to click to Save.
Error due to the Tagging Plan:
If the tagging plan hasn't been integrated with the same attributes on both apps or website, you won't be able to replicate the campaign.