Answer: You can use your trimmer for edging but unless you have a steady hand, you may not make a straight line. Some trimmers have a guide to help you keep a straight line but not all do. You can certainly try, though. Sounds like some of the nylon string is jamming up the retaining cap, preventing you from turning it. Without being able to see it, I'm not sure whether you can work it loose by turning it the opposite way or if you can carefully pry up the cap to release it. I think it would be safest to take it back to the garden center for some assistance in freeing the cap. Good luck with your new trimmer.
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