Why would Jesus instruct a repetitive prayer 2 verses after if (according to you) he rebuked all repetitive prayer?
You are going to have to make sure your opening isn't "Heavenly Father, thank you for this day...." because that would be repetitive, you shouldn't go to church and sing a long to praise and worship songs, because those are just repetitive prayers/praises with music behind it.
That's not what a repetitive prayer is.
praying for the same thing every day is not what He meant
What He meant is repeating the same words multiple times within 1 prayer.
The Rosary is literally an example with all its Hail Mary's
If you can't distinguish a difference between opening a prayer with "Our Father" once in a prayer and 53 utterances of Hail Mary full of grace.... in a single prayer.. then we have basically a language barrier.
Now singing a song is not the same as saying a prayer. Songs are structured to have repeats of certain things obviously, and to some degree, the songs are more for us, to help us remember things because remembering something through a song can be easier than remembering something through just text.
But the Rosary is not a song, it's a prayer, it's a prayer with rote memorized parts that are repeated a number of times.
Now the prayer Jesus taught the apostles, what we refer to as the Lord's Prayer, can be said verbatim there's nothing wrong with it, but more so, Jesus was teaching them a structure what a prayer should be
like
Matthew 6
9 After this manner therefore pray ye: Our Father which art in heaven, Hallowed be thy name.
10 Thy kingdom come, Thy will be done in earth, as it is in heaven.
11 Give us this day our daily bread.
12 And forgive us our debts, as we forgive our debtors.
13 And lead us not into temptation, but deliver us from evil: For thine is the kingdom, and the power, and the glory, for ever. Amen.
The manner is Praise/Adoration first, because remember who you are speaking to, followed by submission to His will, and request for His will and His Kingdom (because without those things what's the point?), then the supplications, first to provide for our needs, as He has already promised, to forgive us for our sins, as He has already promised, and remembering the character in which He desires us to be, to also be forgivers, and then supplication for His protection, which He has already promised.. and finishing off with more praise.
but each line of praise is different.
He didn't structure it like the Rosary is structured, He didn't say it like
"Our Father which art in heaven, Hallowed be thy name. Thy Kingdom come, Thy will be done in earth, as it is in heaven. Give us this day our daily bread. Hallowed be thy name, Hallowed be thy name, Hallowed be thy name. And forgive us our debts, as we forgive our debtors. Hallowed be thy name, Hallowed be thy name, Hallowed be thy name. And lead us not into temptation. Hallowed be thy name, Hallowed be thy name, Hallowed be thy name. But deliver us from evil. Hallowed be thy name, Hallowed be thy name, Hallowed be thy name. For thine is the kingdom and the power, and the glory, Hallowed be thy name, Hallowed be thy name, Hallowed be thy name, Hallowed be thy name, Hallowed be thy name, Hallowed be thy name, Hallowed be thy name, for ever, Amen"
"Hallowed be thy name" is a true statement, it warrants being said. But repeating it set amounts of time accomplishes what? "they think that they shall be heard for their much speaking."