Some of the words in my song titles are not capitalized. Why is that?

Retailers have very strict requirements for content delivery and grammar. For example, words such as “a, an, at, from, for, the” etc., cannot be capitalized unless they are the first or last word of the title. Retailers also require staying away from FULL CAPS ‘unless’ it is in the name of the artist. For example, “LMFAO”.