The problem seems to be that no building on OSM is currently mapped with that postcode. OSM doesn't handle that well, ir just points to an approximate well-zoomed-out area without saying it's approximate. That's fine, but it also puts a marker in the centre of the zoomed out area, therefore being very misleading when zoomed in. The problem with fixing it is that Sea Containers website gives its postcode as SE1 9PD and therefore doesn't provide mappable evidence to allow adding the 9RQ postcode. I've provisionally added it as a point node, but ideally we need to find a business with prominent and externally visible signage to better position it.