Miloud, you need to enter the same details to log in as you used in the previous phone.
Was it a FaceBook attached log in? Was it logged in using the Google profile? Or, was it used entering the Email ID? This is because FaceBook and Google log ins are password less since they are attached to them.
If your phone has the FaceBook logged in, while you were using it, you need to use the same FaceBook ID to log in.
Same goes for the google profile.
If you have used an email ID and password, kindly use that.
Hope this helps.