Joomshopping doesn't accept code

Joomshopping doesn't accept code

Hi, I have a problem with a html code that i would like to insert inside every product.
Actually, I would like to put the tipical paypal button inside Product description.
When I put the code that I copied from paypal website, I can see the button but it doesn't work.
If I put the html code in any other part of the website it works correctly.
Anyone can help me?
thank you

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