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Your LimeSurvey version: LimeSurvey Community Edition Version 6.4.10+240228
Own server or LimeSurvey hosting: Own, PHP 7.4
Survey theme/template: bootswatch
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I have a problem, I am trying to send email invitations for a survey. I've configured a smtp email in the global options and the test email is working correctly, but when I want to send invitations for a survey, the page just reloads and nothing is sent, no error message or something and the invitation check is still not marked.

I've made sure access codes are generated and email status is OK, also tried using default templates, sending only one invitation at the time, switching to php mail is also not sending any invitations while email test works. Installation is new and there are no plugins/extensions activated.

I have no idea what could be happening or what am I missing, any help with this?