JavaScript (ES6), 96 bytes (DIOCL)
`${x="DDDD6IIIII6OOO7CCCC5L"} ${y=`D3D7I7O3O5C9L `,y+y+y+x}LLLL`.replace(/\d/g,d=>" ".repeat(d)) The idea here is to not only make the middle three lines identical, but also make the first line nearly identical to the last. Since there are only 4 letters that perfectly fit this description CDIO, L is the next best option, as it only requires 4 added characters at the end of the string.
As with Florent's answerFlorent's answer, this is a snippet that returns the result. Add 3 bytes if it needs to be a function.
Test snippet
console.log(`${x="DDDD6IIIII6OOO7CCCC5L"} ${y=`D3D7I7O3O5C9L `,y+y+y+x}LLLL`.replace(/\d/g,d=>" ".repeat(d)))