Signal failure

SIR – Recent letters have discussed Britain’s poor mobile coverage.

On Tuesday I was able to speak to my daughter as she lay in her hammock on the deserted shores of Lake Malawi and wish her a Happy New Year. Why is it that I can contact her in the wilds of Africa but am unable to speak to my sister who lives in the wilds of Gloucestershire? James MacDonald

Oundle, Northamptonshire