it looks like this link is unsecure - Facebook

I started a new website Alphasix.ca and have been having troubles with posting on Facebook.

I am getting an error that says:

"It looks like this link is unsecure: alphasix.ca To protect your account, we recommend not posting the link. If you want to share it anyway, you'll need to complete this security check."

I then need to fill out a captcha, and then it posts.

The problem is that once I post it, and someone decides to share it - they then are also prompted with the message and need to enter a captcha.

I went in to the debugger settings of Facebook (https://developers.facebook.com/tools/debug/sharing/?q=http%3A%2F%2Falphasix.ca)

and fixed the OpenGraph issues by configuring Yoast SEO on my website, and creating a Facebook API, but the problem still persists.

It's now giving me an error saying the image can't be downloaded, yet they are displayed at first try there is no problem accessing them, viewing them quickly, or with their file size. I'm not sure if this may be related to this or not.

I've tried searching in multiple places the phrase:

"This link is unsecure"

but have not been able to come up with anything matching those exact words. I did see people with similar problems, but the wording was slightly different.

Facebooks batch invalidator is reporting no problems.

I ran vulnerability scans on the website, and they came up with nothing. I also ran blacklist scans and the came up with nothing.

I have also tried to remove WP Super Cache from my website, thinking maybe it was a caching issue.

This is a new website and domain - Hosted on Google Cloud.

I have spent about 20 hours on this so far, and am no closer to finding a solution.

Any help is appreciated.

UPDATE: in an attempt to have someone else run through the captcha, I had my girlfriend share a post and it worked perfectly fine through the Facebook app. I tried again through my account and no luck. I then tried through a secondary I have for managing pages, and it wouldn't share on their either.

UPDATE 2: I just downloaded the Facebook app and it works fine sharing on there. It seems to be a problem only when using a browser or the mobile website.