I dont know how to explain this but i'll try.

When i try to plug my amplifier into the input hole for the guitar the amplifier jack keeps falling out. I was told that a possible reason could be that an outer ring (nut) is missing from the guitar.

what do u guys think?
Yep, sounds like somethin's loose or missing in your guitar output if that's what you're talking about. I would say take it in to a professional and let them examine it.
take it to a tech. there should be a nut at the end of the jack.
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