close popup JS

I am using the popup builder events, but I would like to know which one allows me to close the modal window. I have tried this, but I haven’t been successful. Any suggestions?
const popupObj = SGPBPopup.createPopupObjById(5361);
popupObj.prepareOpen();

I have tried to close it with these methods but I can’t achieve anything:
popupObj.close();
popupObj.closePopup();

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