-вон- in звонила sounds a lot like -фон- in телефоне, so I wondering if the former comes from the latter.
The reason I don't think the relation (if it exists) can't be the other way around is that it is pretty clear that телефоне, like the italian telefono, comes from greek words τῆλε and φωνή, where the latter means sound.
On the other hand, the action of calling somebody has to do with sound, so I suspect that -вон- might be an altered -фон-.
Using wiktionary etymology:
телефон - ultimately from Ancient Greek τῆλε (têle, “afar”) + φωνή (phōnḗ, “voice, sound”). From Proto-Hellenic *pʰōnā́, from Proto-Indo-European *bʰoh₂-néh₂, from *bʰeh₂- (“to speak”) (whence φημί (phēmí, “to say, speak”)).
звонила - From звон. Pokorny reconstructs the root as Proto-Indo-European *ǵʰwon- (whence Albanian zë), however Derksen holds that the root *swenh₂- (whence Latin sonus) must be considered a serious alternative.
So at the level of Proto-Indo-European they are supposedly different. But going back further in time there could still be a connection.
