Please note, Microsoft support for Office 2016 for Mac ended on October 13, 2020.
Based on my research, version 16.16.20101200 is the final version of Office 2016 for Mac, your current version 16.12.18041000 was released on April, 2018.
You may try the following steps to check whether you could update Office for Mac.
- Download the latest version of Microsoft AutoUpdate tool to have a check. You may get this tool from "More about Microsoft AutoUpdate" which is the last part of article "Update Office for Mac automatically".
- If it does not work, please uninstall Office completely, then click Download links of version 16.16.27 (20101200), install the verison of Office and then check for updates again.
- Besides, you could also try to click Download link for update package of October 2020 release, version 16.16.27 (20101200) to download update packages, check whether you could update to this version directly.
Any updates, please let me know.
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