To troubleshoot connection issues, kindly disable the firewall, proxy or security/monitoring software (anti-virus program) to check, may find this FAQ for the stopper details: -
https://kb.reallusion.com/General/50027/How-to-fix-connection-issue-though-I-was-actually-on-internet
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To fix the "Your <Program> serial number does not belong to this member account" error, please log into your member account that has the mentioned product registered by clicking the "Member Information" button in the top-right area of Reallusion Hub. May reinstall the related program in Reallusion Hub if the problem persists.
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