@lakotaubp @Marathon2422 thanks for your help.
This morning, I tried several things like selected a provider in the APN settings, and then the phone was able to connect to a network.
So now it works well! Very cool!
Last think: it cannot receive mms without data on, which is also the case with my BQ E5. It worked with the Firefox OS and previously with Ubuntu Touch at the really beginning. Do you know why? With 50Mo per month, I use to let the data off, but in this case, I don't know if someone send to me a mms, no notification, nothing, nada...
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