Yahweh used Babylon to punish Judah and the nation. It is either the people of Judah or the people of the nations who are speaking the words in this quotation.
The name of the city is a metonym for the people who live there, and the city is spoken of as if it were a woman. Alternate translation: "the people of Babylon ... they are not healed ... leave them ... their guilt" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-metaphor]])
This can be translated in active form. Alternate translation: "we have not been able to heal her" (See: [[rc://en/ta/man/translate/figs-activepassive]])
Guilt is spoken of as if it were an object that could be made into a pile. The words "to the heavens" and "to the clouds" are an exaggeration for something that is very high. Alternate translation: "For Babylon is so very guilty" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-hyperbole]])