why does it say script can not be loaded?

[narrow pond]

someone please help

[hollow acorn]

did you rename it after creating? open the prefab and try assigning it again (drag it in from project window) - or try reimport all (right click on project window)

[acoustic flower]

You most likely renamed it and did not change its name in script or vice versa. (Remember that you have your script's name before the "monobehavior" line in code)

[slim plover]

most likely is a deleted script or renamed script or plugin is missing