Mira Electric Shower - no water flow

Hi,

Not much of a plumber or electrician but have had a look at my shower and can't see the issue

It's electric and all the lights are working fine. When I pull the cord it clicks okay and when I turn the shower on it does sound like it's trying to get the water but nothing is flowing

I've opened up the unit it's led to see f anything obvious is wrong inside but all seems okay so I'm only led to believe its a water problem and not an electrical one

I've been up in the attack too and everything looks okay there - the tank is full, can't see any issues with pipes or anything

All household taps and toilet are working okay too as far as I can see

Any help (remembering that I am not great at this stuff) would really be appreciated

Thanks