The iD 1000888, 1000088 and 330033 has (and other) been registered and you can not suggest these iDs. Please, remove or change it.
To know if an iD has not been registered, you can use the following link to search for iDs:
http://xat.me/a?id=1013 < Example: just replace the number ID 1013 with the iD you want. This will allow you to identify if the ID you are trying to suggest has not been registered before and so that your suggestion is taken as valid.
or by the bot command: !reg 1013
NOTE: If the ID has b