may Venerable fellows, in front and behind, have the compassion for many to possible correct failures and also fill up graps if traced here.
After having put away foolish thought of believing that equanimity is the highest, even supportive, in such cases:
The first one may do in such a situation, when one gets touched unpleased, better feels that way, is to remind on the very importand Dhammapada stanza, that nobody is of more support as someone pointing out ones failure and in the case of even a wise person, one should stick and hold on such a person.
The second thought is possible given to remind oneself that there are actually very less how would tell one a fault, having other interests in the back and that it is also not so general possible to get the chance of a possible very releasing way for a even personal pardon of a transgression.
Being urged by those reminders one should take all his effort and capacity to reconstruct the case, piece by piece, and most importand, with sacca, ujju!, to get not cheated by ones defilement and miss a great opportunity. Possible ask an admirable friend to help in strong cross-questioning.
If, after real trought-full investigation, it is clear that it's either a missunderstood situation, a unlucky and not right blame, or what ever away from what was fact (done), one does not need to take the given and it will stay his/her's, or as a teacher here once told (a little to quick, on fb), "If someone calls you an ox, look if it is like that, inspecting your back" (retold in it's message, not sure if able to find the original, having been banned because of lifting certain critic on another "lost in short cuts").
The many proper approaches further and for each case, would require all detail case by case actions according the whole circumstances. But as already told by the Sublime Buddha to his son, good to clear such cases with an admirable (dhammika) friend/teacher/guide and it might be that the "insulter" actually is the proper one.
[Note: This here is not given for any worldly exchange, trade, stackes, commercial use, dirct or indirect, and may be needed to be deleted if the circumstances do not allow such gifts.]