Hi,
Have you been to learn-bits tracker, do you try to invite someone before.

I myself tried to invite users but invite didn`t reach them specially users in google domain.I tried to delete invite like this, https://imgur.com/xgPHrX9

My advise is to confirm the user immediately when you invite him because if you tried to delete invite which expired in three days, you will also have no points back like this, https://imgur.com/UxBVFMc

So I think confirming him with ANY way is the ONLY to save invite from descent.

Regards,

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@lamborg please read it