Is it considered forbidden to communicate with a father who used to favor some children over others and failed to meet their needs during childhood, knowing that communicating with him is to please Allah, not out of love for him? And what should I do in this situation?

The rights of parents are immense, and showing them dutifulness is among the most obligatory duties and best acts of obedience, while disobeying them is among the greatest sins. If a father mistreats his child and favors some over others, he is unjust. However, that does not negate his rights over his child. Allah has commanded that even idol-worshipping parents be accompanied with kindness.

It is obligatory upon you to be dutiful to your father and not to cut ties with him. If you fulfill your duty of dutifulness towards him, then your lack of love for him will not harm you. However, you should not surrender to feelings of hatred towards him.