Healthwatch says the EMMA system can't understand some patients in Rotherham.
People are turning to unregulated methods since the NHS withdrew the service say two medical staff.
The warning comes after the closure of a medical practice in Reeth, North Yorkshire, in May.
Scotland's health secretary says it's early days for the scheme and she is enouraged "thus far" - but critics say it should be scrapped.
Lanchester Medical Centre is no longer in special measure but faces more criticism from inspectors.
The medical facility in Hawick is part of a nationwide network aimed at improving access to GP services.
Dr Mat Dorrian says he will work with healthcare professionals with a focus on improving services.
Terry Adams was diagnosed with prostate cancer nine years after first visiting his GP with symptoms.
