Answering the question, Dr. Main  K. Al-Qudah, a member of the Assembly of Muslim Jurists in America, states,

“We need to ask the authors of these words regarding the exact meaning, and to whom the pronouns they use refer to. Also, it should be clear that the following answer does not mean promoting a particular singer or a particular style of songs. It is just a pure answer for your concerns.
1- Using the word (oh) when talking about the Prophet (peace and blessings be upon him) does not necessarily mean we talk to him, because we do the same many times on daily basis when reciting AL-Tashahhud in our prayer, we say (Peace be upon you oh Prophet)
2- Such a promotion and compliment are allowed too, yet, avoiding exaggeration and using controversial statements is better.”

May Allah guide all to what pleases Him!