Either you caught the digimon or you just simply got the common capture error.
If you attempt to capture the digimon when it's yellow bar is almost full, the next attempt of capturing on the same/diff digimon will bring you this error. Just simply press ESC and relogin. The error will not appear again unless you did it again. Just remember, when it's yellow bar is almost full, just let it attack you, it's just some minute damage and won't cause you too much. After it attacked you, try catching again and you will definitely not get that error.