If the Play Store flags it as 'incompatible' then you won't be able to download it from there unless the app's developers modify it (either the app itself or remove whatever spec restriction is being 'flagged' from the Play Store; this can be older OS, specific brand/models, etc.). Your other option is to download the app's APK from a 3rd party (potentially dangerous, especially for a banking app) and side-load it on your phone.