RE: how can I upload again the csv file and erased the old one?
You will first have to bulk delete the existing entries on the Connections : Manage admin page.
Since you are importing a larger number of entries I suggest enabling beta support for CSV Import. To do do this navigate to the Connections : Settings admin page and click the Beta Versions tab. Add a checkmark to CSV Import and save. Next navigate to the WordPress Updates admin page. There is nothing to do on this page but this should force WP to check for updates again. Now navigate to the WordPress Plugins admin page. The beta update to CSV Import should show. Click the Update Now link.
This beta version offers improved speed while importing large files. It also provides more user feedback during the import process.
Hope this helps let me know.
ps. In regards to the phone numbers, on the mapping step, make sure to map the phone number field to the Connections phone number field.