You can add a person to your block list if you no longer want to receive any comments, reviews or information relating to that person in LittleBigPlanet™ and LittleBigPlanet™ 2 or on LBP.me. Adding a person to your block list prevents that person interacting with you and you from interacting with that person in LittleBigPlanet™ and LittleBigPlanet™ 2 or on LBP.me
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Okay, I might have found out a way to resolve the issues which follow along from publishing some levels. I will continue to publish levels but don't expect it to be common. Also, don't try to send invitation requests as the poor performance of LBP3 will make it a grind.