Filtering with VBA Not Quite Working

Hoping someone can help.

I have applied a filter to a value list (Cell C3) using VBA.
This works in fine in that when I select a value from the list i.e. 'Roofs' the data below filters accordingly.

However, when I select a value from the value list (Cell D3) it resets / removes the filter and I don't understand why as there is no VBA associated with this.

Strangely, if you select the value from D3 first, then C3 it works fine also.

Basically I just want the filter to work with what is selected from Cell C3 and not be affected when I select from D3.

Please see attached.

Cheers Steve