Since I buy the domians for my customers, they are all in RC under one single user, so when I imported them into WHMCS using the wonderfull free tool I thought that i had to go one by one moving the service to its rightful owner.
However I saved a lot of time running this query
UPDATE `tbldomains`, `tblhosting` SET `tbldomains`.`userid`=`tblhosting`.`userid` WHERE `tbldomains`.`domain`=`tblhosting`.`domain`
wich looked into the hosting domain of the WHMCS customer and matched it with the one in the domains table.
I hope this is useful for someone.
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