Hello, Anon. We all can be deceived. We are all clay. This is why God gave us so many warnings to beware and be on guard and stay alert. If we were invulnerable to being deceived, there would be no need for these warnings of Jesus and the Apostles. (Thank God so much for them!!)

As to how long to deal with someone (on the internet) who is deceived and supporting these clever wolves: I think that if someone is going to repent of following these ear-scratching teachers, it is going to take time on our part. Remember that we are strangers to them and it takes time to build some amount of trust or respect. I recommend following up only with those who seem sincere in their opposition. Be prepared for possible months-long exchanges. I have had long exchanges that were at first frustrating, then things went better or not so hostile after awhile. At least, if not seeing repentance, there was a softening of their position. The important thing in these exchanges is to follow the admonitions in 2 Tim 2:24-26. Without patience and gentleness and competence the repentance we seek is much less likely to occur.

Stan