Please check whether you are using the AxCrypt portable version or installed version?
Currently, the AxCrypt right-click context menu is available only in the windows (Installer) version of the AxCrypt app. You can see the same by installing the latest version of the AxCrypt app in your windows system.
If you are using portable(standalone) version, please download and install the installable version of the AxCrypt app.
We can find the major differences between the standalone version and installer version of AxCrypt, by clicking the following link: https://www.axcrypt.net/support/faq/#download-version .
or It might be happened because of some firewall/antivirus or other third party applications are blocking the AxCrypt app. So please check the firewall or other software settings.
If the above does not help, Please provide more information about the issue and write a mail to email@example.com . you can send a screenshot showing where the problem is, it often helps us understand.