Not monotonous, it's musical in that there are high/low notes and downbeats, but.. it's as if the "song" was written first and the "lyrics" don't quite fit.

Think of a song that was originally written in English and translated to your home language. You understand the words because they're familiar but some sound weird because they're forced to fit the music. Then think of a clever song written in your own language, often funny songs are a good example, where they start with the idea, and some phrases, maybe some rhymes, and then create and weave the music around the words to bring out the meaning.

Getting the "music" right is one of the hardest things about learning another language, because we learned and babbled the tune of our own language before we even spoke it.

As a step, make sure to learn the syllable(s) that get the hard accent in each word, and stick to it every time. Because English is such a jumble of stolen words and phrases, it's not consistent about which part of (for instance) three-syllable words gets the beat, but it is pretty consistent about each individual one.

Edited to put in some beats, and highlight the accented syllable in the long words. The bold isn't stronger than the italic, it's just a different purpose.