Photostream problem in Photos App

Dear Apple Community

Since few weeks, I have a little problem : new photos taken with my iPhone don't appear automatically on my MacBook Photos application (it was the case previously) : now, to see the new photos, I have to completely restart the MacBook and then, new photos appears in the photostream album (photostream option is activated on my iPhone and through the iCloud parameters on my MacBook)

I use last version of iOS et OS X El Capitan.

Can somebody help me please?