By "not moving", do you mean the actual tape part (not the posts) just wasn't there? Or it was there, and just kinda sitting in place?
If the former, most either the tape couldn't spawn due to too many other sprites (specifically, permanent sprites which can't normally be replaced like P-switches or springboards). Try reducing those kinds of sprites.
If the latter, then it's something else. I've never seen a glitch like that with the original game, so it might be related to any patches, blocks, sprites, or UberASM code you have used. If you have a list of those, it'd help identify the cause.
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