My enrollment button does not show up on safari

On google chrome my course shows up correctly with a button to enroll. When using Safari it shows up with a button to sign up. After submitting all the info on the sign up page it does direct them to the check out page but I want it to show up the same on all web browsers.

Also there are times when I select enroll and my it states my cart is empty.

Why is that?

I'm loosing conversions because of these issues.

Can anyone help?

PS. I have cleared all cache and cookies before trying