Правило из учебника Advanced Grammar in Use:
"Some verbs used as performatives with the present simple in affirmative (= positive) sentences (apologise, deny, guarantee, promise, suggest) have a similar meaning with either the present simple or the present continuous in negative sentences:
I don't deny/ I'm not denying taking the books, but Miguel said it would be ok."
Не могу ни перевести внятно, не уловить смысл, в чём особенность употребления :donno: