Is it permissible to pray behind an imam who elongates words and recites in a manner resembling singing, and does his action of placing his palms on his forehead after the prayer and saying "Ya Hayyu, Ya Qayyum" seven times have any basis in religion?

Improving one's voice during recitation is desirable, and it is the guidance of the Prophet, peace and blessings be upon him. He praised Abu Musa al-Ash'ari for his beautiful voice. However, the recitation should not deviate from its proper context or resemble the tunes of the immoral. It is permissible to improve one's voice as long as it does not alter the meaning of the words. As for the imam's action of placing his palms on his forehead and saying "Ya Hayyu Ya Qayyum" seven times after prayer, it is a reprehensible innovation (bid'ah munkarah) that has no basis in Islamic law, and he should be advised to abandon it. Praying behind an innovative imam is permissible if his innovation is not polytheistic (shirkiyyah), but it is preferable to seek an imam who adheres to the Sunnah. If the imam insists on his innovation, there is no objection to working to prevent him from leading the prayer.