Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Thank you for posting your question in the Microsoft Q&A forum.
I’d like to confirm and add a bit more context beyond what the Q&A Assist has already provided. Office LTSC Professional Plus 2024 is not a product designed for home or individual use. It’s sold exclusively to organizations through volume licensing channels. This means that volume license keys such as MAK or KMS are intended only for businesses with proper agreements in place.
When these types of keys are resold to individual consumers, usually through unofficial or unauthorized retailers, they may appear to work for a short period. However, once Microsoft’s activation servers detect that the key is being used outside of the legitimate volume‑licensed environment, the activation is automatically revoked during routine checks. This is why your Office software was initially activated but later began showing “not activated” even though you were using it normally before.
If you’re using this product as a personal user, the best next step is to contact the retailer who sold you the key and ask them for support or a resolution. Since the issue comes from the source of the product key rather than anything on your device or account, they are the ones responsible for helping you address it.
Alongside that, I’d also suggest taking a look at the official options available here: Compare Microsoft 365 Plans & Pricing – Microsoft Store. You can consider these plans as a long‑term and fully legitimate solution, ensuring you’re using a product designed for individual users and backed by proper licensing.
Thank you again for reaching out, and I hope this information helps clarify things for you.
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