Paypal redirection doesn’t work

Hello there,
i’ve build a paypal form where the user can send money. But if i click the submit button there’s no redirect to paypal.

This is what i’ve found in console log:

Access to XMLHttpRequest at ‘https://www.paypal.com/cgi-bin/webscr?currency_code=EUR&business=test%40gmx.de&cmd=_cart&notify_url=https://streammax.de/wp-admin/admin-ajax.php?action=checkpaypal%26form_id=9%26nonce=6ca4e22206%26group_id=65&upload=1&charset=UTF-8&item_name_1=Virtuelles+Ticket+w%C3%A4hlen%3A+Ticket+f%C3%BCr+5%E2%82%AC&amount_1=5&quantity_1=1&return=https%3A%2F%2Fstreammax.de%2Fwp-admin%2Fadmin-ajax.php%3Faction%3Dfm_submit_form%26current_id%3D9%26formType%3Dembedded%26succes%3D1589439515’ (redirected from ‘https://streammax.de/wp-admin/admin-ajax.php?action=fm_submit_form&current_id=9&formType=embedded’) from origin ‘https://streammax.de’ has been blocked by CORS policy: Response to preflight request doesn’t pass access control check: Redirect is not allowed for a preflight request.

Can you help me?

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