@Passport2Reality was this sit confirmed before Sep23 ? Since that time it should not be possible for a member to turn off auto renew without first cancelling their confirmed sit ( see post below )
Another explanation is that the member has been removed from the platform by THS . However if a member has been removed from the platform member services should have contacted all confirmed sits to inform them .
Please let us know the outcome when you have spoken to member services . As @Twitcher already said can ask to chat with a human on the live chat 
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