Giving Reasons According To Situation Hurting No One
In my opinion, if it is certain that the manager is unreasonable and it may be an immediate threat to your job or career, then Allah is forgiving. For a longer run, it may be better to look for a position somewhere else. Still, I think it is better to state the truth and trust Allah. If you trust Allah, even if you lose your job here, you may find a better one; just because you trusted Allah.