All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
The Salat Naria that you referred to in the question was not reported from the Prophet . Moreover, it contains some false meanings that contradict the Sharee’ah. In fact, Allah is The Only One who unties the knots. Allah is The Only One Who eases the sufferings. It is He Who satisfies the needs. Allah Says (what means): {Is He [not best] who responds to the desperate one when he calls upon Him and removes evil and makes you inheritors of the earth? Is there a deity with Allah? Little do you remember.} [Quran 27:62]
Think about this and the meaning of the following Hadeeth:
The Prophet once said to his daughter Faatimah and other relatives: “O Bani 'Abd Munaf! Buy yourselves from Allah; O Bani 'Abdul-Muttalib! Buy yourselves from Allah; O mother of Az-Zubayr ibn Al-Awaam, the aunt of Allah's Apostle, and O Fatimah bint Muhammad! Buy yourselves from Allah, for I cannot avail you anything before Allah. You can ask me from my property as much as you like.”
As for the sound way of asking blessings for the Prophet it is what he (the Prophet) himself said when asked: Imam Bukhari narrated in explanation of this verse that Ka'b ibn Ujrah said, "We asked the Prophet saying, 'O Prophet of Allah! How should one (ask Allah to) send blessings on you, the members of the family, for Allah has taught us how to salute you (in the prayer)?' He said, 'say: (اللهم صل على محمد وعلى آل محمد، كما صليت على آل إبراهيم، إنك حميد مجيد. اللهم بارك على محمد وعلى آل محمد، كما باركت على آل إبراهيم، إنك حميد مجيد) “O Allah! Send Your Mercy on Muhammad and on the family of Muhammad, as You had sent Your Mercy on Abraham and on the family of Abraham, for You are the Most Praiseworthy, the Most Glorious. O Allah! Send Your Blessings on Muhammad and the family of Muhammad, as You had sent your Blessings on Abraham and on the family of Abraham, for You are the Most Praiseworthy, the Most Glorious.' It is narrated in another narration that Abu Humayd as-Saidi said: “The people asked, “O Prophet of Allah! How shall we (ask Allah to) send blessings on you?” the Prophet replied, “Say: (اللهم صل على محمد عبدك وعلى آله وأزواجه وذريته كما صليت على إبراهيم وآل إبراهيم، وبارك على محمد وآله وأزواجه وذريته كما باركت على إبراهيم وآل إبراهيم إنك حميد مجيد). “O Allah! Send Your Mercy on Muhammad and on his wives and on his offspring, as You had sent Your Mercy on Abraham's family; and send Your Blessings on Muhammad and on his offspring, as You had sent Your Blessings on Abraham's family, for You are the Most Praiseworthy, the Most Glorious.” All these forms are correct.
So, the prayer that you mentioned is null and a bad innovation that is incorrect and impossible to be from the Prophet. Even its name Naria (part of Hell-fire) is a clear evidence that it is from ignorant, fairy storytellers and innovators. So, one should enlighten people about this innovation and cease repeating it if he used to say it. He should also repent to Allah and ask forgiveness from Him, and worship Him with what He has revealed to His Prophet, not with myths and innovations.
May Allah protect us all from these innovations.
Allah knows best.