The variations of the word "cancel" can be written in the different ways, depending on the countries.
- Canceled is used in USA
- Cancelled is normally used in United Kingdom, Canada and Australia.
Both forms are correct in English, but in Atexto we've standardized the American usage of words.
This means that for words like Canceled, Cancelation, Canceling, we'll use the US English form of the word, with a single L.
There are other verbs that will use this same rule, for example, Level and Travel, and some of their variations are leveled, leveling, traveler, traveling.