Please provide the following information:
Operating system version = OS Mac Sierra 10.12.6
Web browser and version = Safari Version 12.0 (12606.2.11)
File name of the installer you are using = ? Adobe?
Flash Player version <https://forums.adobe.com/external-link.jspa?url=http%3A%2F%2Fkb2.adobe.com%2Fcps%2F155%2Ft n_15507.html> = ? Never gets far enough to check
Explain your problem in step-by-step detail if possible = Gets to 90% installed then stalls (message is = Adobe Flash is NOT responding)
A direct link to a web page that demonstrates the problem = n.a.
If you get error messages, please provide a screenshot <https://forums.adobe.com/docs/DOC-7043#jive_content_id_How_do_I_attach_a_screenshot>
Please provide Adobe_ADM.log and Adobe_GDE.log files. You can get the location of files from Where do I find the Flash Player installation log on the Macintosh? link. Once you have the files, upload the same and share the link here. Refer to How to share a file using Adobe Document Cloud to know how to upload files.
In the meanwhile, please use the offline installers available on Installation problems | Flash Player | Mac page under 'Still having problems' section.