Widget Script for Booking Gift Cards

Hi,
i want to integrate a gift card from booking tool (SimplyBook) in my Enfold Website.
I got this info from simplybook: It currently works with iFrame widgets only

I have tested Codeblock, Text with iframe… I does not work. It shows nothing.
A test in an other wordpress theme was direct succsessful. It shows as demo a blue Icon.

Can you help me?

Here is the Widget Code:
<script src=”//simplybook.it/v2/widget/widget.js”></script> <script>var widget = new SimplybookWidget({“widget_type”:”iframe”,”url”:”https:\/\/demo.simplybook.it”,”navigate”:”gift-card”,”theme”:”default”,”theme_settings”:{“timeline_show_end_time”:”0″,”timeline_modern_display”:”as_slots”,”sb_base_color”:”#0cadef”,”display_item_mode”:”block”,”booking_nav_bg_color”:”#80d0f2″,”body_bg_color”:”#f7f7f7″,”dark_font_color”:”#494949″,”light_font_color”:”#ffffff”,”btn_color_1″:”#5e7da7″,”sb_company_label_color”:”#ffffff”,”hide_img_mode”:”0″,”show_sidebar”:”1″,”sb_busy”:”#dad2ce”,”sb_available”:”#0cadef”},”timeline”:”modern”,”datepicker”:”inline_datepicker”,”is_rtl”:false,”app_config”:{“predefined”:[]}});</script>

Dokumentation:
https://help.simplybook.me/index.php?title=Widgets_for_your_own_website&mobileaction=toggle_view_mobile
scoll down to “Widgets for Client Login, Packages, Memberships, Gift Cards”

Best regards Ralf