The forums in which I participate include representatives of a variety of communities of faith. It is extremely easy to get into pointless arguments about finer points of doctrine that contribute nothing to the support requests that form the backbone of what the forum is there for. It is also very easy to cause offence.
If you must stand by what you believe, it’s a good idea to be sensitive to any rules that those who run the forum have put in place, otherwise you run the risk of being banned. It might be necessary to quietly take your thoughts to an alternative venue for discussion. If you identify as “Christian” you might well to apply the principle underlying Romans 13:1 – in short, work within the rules, and not contrary to them.