The Fastify JSON Schema and Zod validation for PUT /api/admin/settings only accepted string for communityDescription, communityLogoUrl, primaryColor, and accentColor — but the GET response returns null for these fields when unset. The frontend round-trips the null values back, causing Fastify's AJV to reject the request with a 400 before the handler runs. Align both validation layers with the database schema by adding null as an accepted type, matching the existing pattern used by jurisdictionCountry. Fixes barazo-forum/barazo-workspace#TBD