what's wrong with my function?

tick.mcfunction... execute as @e[type=marker, nbt={data:{commandmarker:1b}}] at @s run data modify storage commandmarkers:commandbuffer main set from entity @s data.commands function commandmarkers:commandloop ...calls commandloop.mcfunction. execute if data storage commandmarkers:commandbuffer main[0] run return data modify storage commandmarkers:commandbuffer2 main set from storage commandmarkers:commandbuffer main[0] function commandmarkers:command with storage commandmarkers:commandbuffer2 data remove storage commandmarkers:commandbuffer main[0] function commandmarkers:commandloop Command.mcfunction reads $execute as @s at @s run $(main).
There appears to be an issue with commandloop.mcfunction, as it displays an error when ran. Unfortunately i don't know what's wrong with it, as minecraft simply just says that it doesn't exist. any help?
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