A month ago, I transferred my website from HTTP to HTTPS and completed all necessary modifications, including implementing a 301 redirect to redirect all old links to the new HTTPS version. I also added the HTTPS version to webmaster tools, submitted a new sitemap, and updated all internal links to use HTTPS.
Everything appeared to be working fine, as my website's links in Google were updated to HTTPS, and the visits to the HTTP version decreased every day. However, I was surprised to find that my links in Google reverted to HTTP, and visits to the HTTP version increased day by day, despite the 301 redirect functioning correctly.
I'm now unsure of what to do to make the links appear in HTTPS version in Google.