Photos lost from the gallery. OnePlus 6

[Android Central Question]

I had been on a short trek to the nearby mountain range and managed to click some amazing pics on my OP6. But to my horror, all the pics clicked between a 3 hour interval are lost!! I've even viewed these pics after I clicked them. But when I was scrolling through all the images, noticed that for than 80% of the photos have disappeared. Only the first 10% and the last 10% are present. I have checked the deleted items folder and also all the folders where images are stored in the phone using file explorer. Do not find the pics anywhere. I started clicking photos at around 10 AM and carried on till 4 AM. But all the photos and and videos clicked between 11.27 AM and 2.27 PM are missing. It's as if I did not use my phone at all for these 3 hours. I have even restarted my device to check if that would work. I still can't find them and this is just ridiculous thing to happen on a flagship device. My trek buddies will never forgive me if i can't recover the photos! This looks like a major reliability issue with One Plus 6. You never know if this repeats again. Please provide a solution if there is any way that I can recover these photos.