It may be the tagging, I'm not sure why. But at 1 John 5:18 in the NA28, L5 cannot find ἑαυτὸν in the BDAG lexicon. It's there if I manually search for it, but double clicking on ἑαυτὸν in the text or even using the contextual menu will not call up BDAG for the lexical form of ἑαυτὸν.