Translation:My neighbour worked in Saint Petersburg all autumn and all winter.
In this context the accusative case is required, so всю agrees with the feminine accusative весну (spring), осень (autumn) and зиму (winter), but if we wanted to use the word for summer it would be the neuter всё лето and if we wanted to say all day then it would be the masculine accusative весь день.
Hope that helps
The current array of correct renderings of the sentence may not include your variant. Normally if it conveys the same meaning and you select the "my answer is correct" option, the team will give it due consideration before adding it to that array for future use (or not). In this case the app was probably expecting the use of 'all' rather than 'throughout '.
Hope that helps.