DataScraping and uipath_custom_id missing for some rows


I have a problem with data scraping. I figured out that for some rows there are urls but other data is missing. In normal case I have 2 columns - one is a text and second is url. For some rows there are only urls but no text. I checked html and found that for this rows attribute uipath_custom_id is missing for some reason. Anyone faced similar problem?