In Hebrew the verb’s gender should agree with its subject and number. The word “Qohelet” is a feminine singular participle functioning as a noun. So the word requires feminine singular forms of verbs. However, because Qohelet is introduced as a “son” of David, almost all verbs for Qohelet is masculine singular except for Eccl 7:27, which seems quite intentional and worth giving your attention.
Wisdom and Poetic Books, 지혜 문헌과 시가서