[Vivo Y93] My phone's bootloader was unlocked

My phone's(second hand) bootloader was unlocked even though no one ever touched this phone(except my parents when they needed to do some banking stuff) since my parents bought this. I think this is malware since i downloaded a modded game before this happened, but my friends don't think so since they say unlocking a phone bootloader would require my phone connected to a PC physically. My family don't have a PC, and neither are they tech-savvy enough to know about bootloader and other software stuff. This phone's bootloader wasn't unlocked ever since this phone was bought until now(bank apps were working normally), and i don't know how it got unlocked, the only reason i found out about the bootloader being unlocked was because banking apps were not opening. I ran the modded game file through virustotal and bitdefender(free) and it said it's safe, and I haven't touched since i downloaded it before deleting it. Is it really malware, if so how do i remove it? Or is it something more serious or not that serious?