How do I know that the procedure to keep my number has been successful? that the portability was correct

During the processing process, you will see that the status of your Fax number is "pending".

Until such portability processing is not effective, you can only "send faxes" from eComFax, the reception will continue without variation in your old device until the portability is completed.

When the portability has finished correctly, automatically, the status of your Fax goes to OK and therefore you will start receiving your faxes in eComFax and you can use the service to send and receive faxes.

From that moment you can unsubscribe your old line if you wish and you only need to use eComFax to send and receive faxes.