The impersonal pronoun "Il" is the subject of the first clause and the verb « se passer », une journée is the direct object, and as it follows the verb, there is no agreement with the object.

A couple of links: 

Conjugate reflexive verbs in the present tense in French (Le Présent) 

https://www.lawlessfrench.com/grammar/agreement-with-pronominal-verbs/

Hi Chris,

My understanding of the translation is something like "Not a day goes by without her making (doing) the (la) face"

So "elle" belongs to the subordinate clause introduced by the relative pronoun "que".

"ne" is expletive.

This is how I see it  --  I look forward to others' comments though.

Jim