Adding Paypal Buttons
 

I am trying to add a Paypal Donate button to our nonprofit website. I have created the button on Paypal and pasted the source onto a page. When I click the "update" button* the Paypal button I inserted is there fine* but when I click the "save page" button* the Paypal button disappears! I am about to pull my hair out over this!!!!

PLEASE help with a resolution! I am sure this is very simple* but for the LIFE of me* I can't figure it out!