I am considering body treatments because the fat on my arms just won't go away even with exercise.

When I diet, I lose weight little by little, but strangely, my arms just stay the same, which is a huge concern for me. My upper body is on the thinner side, but my arms look particularly thick, so I get even more self-conscious when taking photos in short sleeves or sleeveless tops. I’ve tried exercising, and while working out hard does make my arms feel firmer, it doesn't seem to reduce their size as much as I want. So lately, I’ve been looking into body treatments. However, there are so many types—fat-dissolving injections, Body InMode, radiofrequency, cryolipolysis, etc.—that I don't know what to look for. I'm not looking for weight loss itself, but rather just to refine my arm lines a bit so they look less bulky when I wear clothes. I'm wondering if body treatments are commonly performed for this kind of situation. Also, I heard that the treatment varies depending on whether the issue is due to excess fat or simply swelling or skin elasticity; will they be able to differentiate this during a consultation? I'm worried that injection treatments might cause long-lasting bruising or swelling, while I'm concerned that non-injection treatments might have minimal effects. Since I plan to get these treatments while working, I'd prefer something that doesn't interfere with my daily life. I am curious to know which procedures those of you who have received body treatments to refine the lines of specific areas, such as your arms or flanks, chose. I would also like to hear if there are actual experiences where your body looked different even though you didn't lose much weight!