While the phrase "Happy Marriage Anniversary" is commonly used in some parts of the world, it is not the most grammatically correct way to wish someone on their wedding anniversary. The more standard and grammatically appropriate phrases are:
Happy Anniversary: This simple and concise expression is widely used and understood to convey good wishes for a wedding anniversary.
Happy Marriage Anniversary: While not strictly incorrect, this phrase is less common and might sound a bit redundant. Most people prefer to use "Happy Anniversary" or "Happy [X]th Anniversary" instead.
Happy Wedding Anniversary: This phrase is also acceptable and explicitly mentions the occasion being celebrated.
Congratulations on Your Anniversary: This is another way to offer good wishes on a couple's wedding anniversary.
Remember that language usage can vary in different regions and cultures, so you may come across variations like "Happy Marriage Anniversary" in specific places. However, if you want to stick to a more universally accepted and grammatically sound expression, go with "Happy Anniversary" or "Happy [X]th Anniversary."