Accuracy of Tide data

I’ve just purchased a Instinct Solar Surf watch specifically for the tide data.  I’m finding that when inputting co-ordinates of the location i want, the displayed location is local but not the same as the data for the specific location.

E.g.

- I want tide data for Ventnor Beach, Isle of Wight, UK

- I input co-ordinates for that location and the data it finds says location is the Isle of Wight (but not anything more specific).  There are 12 tidal stations on the Isle of Wight so it doesn’t say which one it is displaying.  

- The data shown is at least 30 to 60mins out for each low/high tide reading - i.e. wrong

I’m trying to understand if this is something that can be fixed as it defeats the purpose of purchasing the watch,  I’m sure the data is being pulled from some international database somewhere but I can’t figure out where to look to check accuracy or resolve this.  It would be a shame if the tide data Garmin uses doesn’t access these 12 Isle of Wight tidal stations.  Is it only large and popular tidal station locations that it will pick up?

I must admit, I’m toying with the idea of returning the watch as if its not accurate, why have it.

Can anyone tell me where to look to check the Garmin data accuracy.  Thanks