Audio out of sync after importing EVEN AFTER using Handbrake

Let me start by saying that I'm a new(ish) user of Adobe Premiere Pro. I am absolutely exhausted of Googling and searching high and low for answers. I am simply compiling clips of my singing for a music competition--no fancy effects or graphics involved. My original video clip looks and sounds fine on its own but when I import it into Adobe Premiere Pro, the audio gets out of sync. I have tried using Handbrake to encode my clip at "Constant Framerate" and while that did help a bit, it's still not 100% synced. I tried encoding at 30 FPS, 29.97 FPS, and even "Same as source". Also, the exported video is generally more out of sync than what I see in Premiere Pro, so I'm always in for a surprise.

I've tried other shortcut tricks like changing the file name from .mp4 to .mov but it didn't help. I tried creating a new project from scratch with the hope that a blank slate would erase any past issues. But no luck.

I'm really frustrated and disappointed. I would expect that a high end software like this would make video editing a breeze.

This matters a lot because the video is myself singing (a fast, upbeat song in fact) for a competition and it's quite obvious when my lips don't match the audio. I don't want anything to allude the adjudicators of lip synching.

I'm beginning to contemplate if I should switch to inShot or resort to the Video editor app that came with my laptop (which actually lowers the audio quality of the exported video)...

Details (if this helps):

Windows 10 user

Type of file: MP4

Video details

Frame width 1920

Frame height 1080

Data rate 16988 kbps

Total bitrate 17244 kbps

Frame rate 29.99 frames/second

Audio details

Bit rate 255 kbps

Channels 2 (stereo)

Audio sample rate 48.000 kHz

Your help is greatly appreciated.