Have you purchased a heat defiant (HD) wig/topper "thinking" it would hold up better, because after all if it can withstand heat up to 350°F shouldn't it withstand the heat at my neckline??
I was so disappointed the first time I wore a HD wig. It was great for about a month, but then the ends started frizzing like I had split ends. The worst part was it was sooo itchy on my neck. Frizzing is caused by heat friction ... the rubbing of your piece against your skin, typically your neck area. It's very important to use a wide tooth comb everyday to gently comb out your hair when you are done wearing her.
Don't give up on her .... here are some simply tricks to help rejuvenate your HD piece.
Use a professional flat iron with a digital temperature setting at 270-280°F to smooth the fiber. Keep in mind when you flat iron your wig you are changing the style. If your piece is straight, no worries. But if your piece is curly or wavy, you will need to style her again. Remember HD fiber must be cool set to take the curl.
If frizzing is excessive, use a steamer to smooth the fiber, followed by a flat iron set at 270-280°F. The steamer will give it the extra moisture to rejuvenate your piece. The advantage to using a steamer over a flat iron is you can style her while you are steaming her, for instance with a round brush or even velcro curlers.
Watch the below video by Jon Renau.