Paypal Donation Button problem

I added a Paypal donation button to my Donation page, but the link is not working. The button shows up, but the link doesn’t work. I copied the html code from Paypal and pasted it to the “code” editing section of the page.

I used the exact same code for the button on my sidebar and it works perfectly fine. I noticed that when I go back to the review the code on the page, it changes automatically and bunch of the information is deleted. The code is shortened from the original code.

Can anyone tell me what is wrong and how to fix it?

Here’s the url:
http://trishalim.com/?page_id=4

Thanks.