What is the ruling on seeking protection with the mentioned supplication?

The statement that a specific charm protects its reader from evil throughout the day is a false claim for which there is no evidence. Such knowledge can only come from an infallible text from the Quran or Sunnah. This claim is an assertion about Allah without knowledge. One must be cautious of such claims and attaching one's heart to vague and contrived phrases. The greatest protection is the Quran and the authentic supplications from the Sunnah. The aforementioned supplication contains strange phrases such as "by His beautiful names I am enveloped," "the luminous letters," and "admit me into the secret of the flow of the lights of the treasures of Your charm." These are innovated words unknown to the Salaf, and they may carry invalid meanings. They should be replaced with authentic prophetic supplications.