Conflict with MailPoet

If I run the MailPoet shortcode [mailpoet_manage_subscription] WITHOUT the UM plugin active, the MailPoet update works fine.

If UM is active, however, a normal member cannot update their MailPoet settings (they get redirected to the site homepage). However, an admin CAN update their settings.

So somehow UM is conflicting with MailPoet only for normal members.

Can you help?