Clicking to visual tab Messes this up.

This is the correct topic title…………
I am switching from PayPal to First Data to handle my credit cards.
First Data had a code generating thing that too my info and made a button.
I put the Code in the text tab and hit update. I checked the site and it worked correctly.
Here is the problem…..
I hit the visual tab and it was the wrong color. I went back to the text tab and about half of the code disappeared. If I hit update again I get the wrong color button and the button doesn’t work on the site.
So whenever I hit the visual tab something eats part of the code I put in.
Any ideas?

Also, If I change anything on the visual tab the Paypal dropdown buttons get messed up. But I worked around that by re-putting the code in in the text before I hit update button. That problem was always