Creda T622CW tumble dryer No heat?

I have a Creda T622CW tumble dryer and there is no heat at all on the low setting. If I dry clothes on the high setting it takes much longer than it used to but there is heat and it struggles to dry the full load on 120 mins. Does this dryer have 2 heating elements and maybe one has went or would it be thermal cut out switches which seems strange if there is heat on the high setting.Any help would be appreciated.