Last time I installed a BMX sprocket it had a lockring to keep it tight side to side and a hole in the sprocket which a pin locks into to stop it moving rotationally. It sounds like the lockring isn't done up properly.
Pictures would help.
@IdealStandard started
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Last time I installed a BMX sprocket it had a lockring to keep it tight side to side and a hole in the sprocket which a pin locks into to stop it moving rotationally. It sounds like the lockring isn't done up properly.
Pictures would help.