Word checks a new document but skips spelling mistakes in one template-based file

Make a copy and inspect the proofing properties of one affected paragraph. Check its selected language and whether it is marked to skip spelling and grammar. Interface language does not necessarily replace proofing metadata attached to pasted text or a template.

Run a small deliberate-error test after the targeted correction. For a multilingual document, preserve the intended language of each section rather than assigning one language everywhere. Confirm the product and language’s supported proofing features if grammar or refinements, rather than basic spelling, remain unavailable.