Rockyhudson

Hi there.we have a vanguard hottub and having problems with it not heating.we had one guy come round saying it was the heater .so borough one and he fitted it and still the same.then wouldn't reply to my messages.got another guy out said it was the heater board so again replace that one and still no heat.i have had a look myself and when I have taken the front cover of the red light is blinking on the heater board. Could anyone help please as it's been going on over 14 months now.people just taken money from me.thank you