Android phone unresponsive touch

I have had my Vivo Y20i for 2 years now. But this past 6 months, I've been experiencing some touch issues where part of my screen doesn't respond to my touches, and to make it work again is to lock my phone and then unlock it and everything works as normal. Sometimes it takes 2 to 3 unlocks before it returns to normal. It's pretty irritating especially when I'm playing something or typing something, doesn't respond to my touches, and sometimes ghost touches. The time it occurs is random. I do not have any applications that can alter any touches or systems whatsoever. I only have the default apps (YouTube, Google, Etc.) and Mobile Legends. And I haven't dropped my phone since then.