The correct phrase is "insists on." The phrase "insists of" is not correct and does not exist in English.
Example: The teacher insists on good behavior in her class.
He was accused — wrongly, he insists — of stealing nearly a million dollars of Luchese family money.
"It's not about making the ordinary extraordinary," Weeks insists of the finished collection.
"As a worker, she is in no way a diva," he insists of Toni Morrison.
"I'm not a coach," Vogts insists of his brief American involvement.
He insists of his often lovelorn lyrics: "I don't write from my own personal experiences – they're observations.
She is unaware, she insists, of more recent acts who have cited her band as an inspiration.
And the philosophy of history insists on a conception of history as a whole.
"They've done everything," she insisted of the group.
However, despite the current environment of fear and caution, he insisted: "Of course I am optimistic.
"I was prepared," Ms. Eisenberg insisted of her most recent business trip.
"Looks fine!" he insisted of the last few dreads still clinging on.
