If an Austrian LSA account is approved but not getting leads, first you need to check whether the ad is actually serving and whether the targeting is too restrictive. Review the budget, ad schedule, business hours, service areas, and job types, since these settings directly affect when and where your ad can appear.
Also check that the linked Google Business Profile is verified and properly connected, and that your Austrian business registration and other required verification details are complete. Google specifically lists the Umsatzsteuer-ID-Nr. as an accepted business registration document for Austria.
If everything is set up correctly, look at local competition, reviews, service demand, and budget. An approved account does not mean your ad will appear for every relevant search.