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Add products to your cart and remove them from here Lets buy❓ What does the "Missing translation" warning mean?
#Answer
The plugin looked for a line in your active language file and did not find one, so it fell back to English.
It is a warning rather than an error, and nothing breaks. It usually happens after an update that added new messages, since your existing translation file predates them.
#How to fix it
The warning names the missing key. Either add that key to your translation file under translations/, or, if you have not customised the file, delete it and restart so the plugin writes a fresh, complete one.
Deleting the file discards any wording you changed. Take a copy first if you have edited it.