A volcano speaks of intercessory prayer which removes mountains through travail to obtain a spiritual breakthrough.
Cellphones speak of communication, in this case, with God (prayer, two-way communication)(with God because of the cellphones being linked to the volcano and also because of the white color). The phones were white which speaks of victory and breakthroughs.
I do not know what triggered the dream. Yes, it was the fact that you watched the events on Iceland and La Palma, but, you must have asked God some questions about the events, even if you are not really aware of it (subconscious mind).
I suspect that either the events at Iceland and La Palma were natural phenomena being a revelation of what is going on in the spiritual realm, or God used it to reveal some kind of comparison to your attention (natural vs spiritual)
Sometimes, in the natural, things happen automatically because of certain reasons (influences) but in the spiritual, we can have the same results (emphasis on breakthroughs because that is what volcanos represent) through intercession and prayer. Do you or your family members need a breakthrough at the moment? Does the church need a breakthrough? This is the answer (intercession and prayer). The many cellphones speak of a multitude so I suspect that this is about the church, or people in general (even the residents of those countries) because they certainly need breakthroughs because of the financial complications of the volcanic eruptions.