No more email reminders?

Hello!
I love your plugin and have been using it a lot for my students to sign up for conversation sessions. However, I noticed lately, that it stopped sending the reminder emails to the registrants… They used to receive one one day before and 3 hours before the meeting. Now I have to send the link manually… What can I do to get these emails back? I didn’t make any changes in the settings, they just stopped being sent… but they are very important!
Many thanks, best regards,
Juliane

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