Ref. No. 41/1058
In the name of Allah the most gracious the most merciful
The answer to your question is as follows:
It is duty of a husband to fulfill all the requirements of his wife including medicines etc. A wife should always inform her husband about her necessities and he should try his level best to fulfill them. If husband neglects them whereas he is able to do so, then she may take requisite amount even without his permission in an unavoidable case as it is her right. Phone bill is not included in the list of necessities.
And Allah knows best
Darul Uloom Waqf Deoband