There should be an option to block these team invite spammers and team joining spammers from just messing with you while you are trying to form a team. There should also be an option to block whispers from random strangers before they even whisper you. Some know when to give up but the needy ones just keep spamming you with annoying requests for help and it gets really tiring when you get multiple requests for carry from people whom you don't even know and have rejected and despite that decide to force themselves into your team.