sheila secker , 78 , had been given the pay-as-you-go phone by her son , but as she had not used her pay-as-you-go phone for some time it had been cut off .
when the grandmother collapsed in her home in december , she could not contact her family and died in hospital a few days later , the sunday times reports .
as sheila secker had not used her pay-as-you-go phone for any chargeable services , vodafone retired her number without warning .