Invoicify is not a known or established software application for Windows (or any other platform). There[SQ]s no widely available information about a program with that name. It[SQ]s possible :

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The name is slightly misspelled:

Try searching for similar-sounding names, perhaps with variations in spelling.
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It[SQ]s a very niche or newly developed program:

If it[SQ]s a very small, recently released application, it might not have a broad online presence yet.
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It[SQ]s an internal or custom-built application:

The software might be used only within a specific company or organization.
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It doesn[SQ]t exist:

The name might be incorrect.

If you have more details about where you encountered this name (e.g., a website, advertisement, conversation), it might help in finding out what it is.