Looking at your profile, the first two games you were matched with, and lost to other B4/5 players. That in itself doesn't help, as the early matches help determine later placement matches.
To be matched that low early, it would suggest that you have played TT in S7 and were already Bronze. It sucks but placements are lower than normal, the idea is you will climb back to where you belong.
If you want some advice, something you can do is to organise your builds smarter. I can see by just glancing at your games that you have a particular core build for that champ and don't move from it, even when it isn't efficient for who you are up against.
A key example for a Maokai game I can see is you like to build Iceborn Gauntlet. It's good in general on a Maokai, but up against a Brand and Veigar it's not the best item as the item proc requires you to get close, and without MR you will be shredded trying to do so. A better item there is the Abysal Mask. Gives you MR + HP, and enhances your magic damage for when you do engage (And for the team comp you had, you needed to be the peel for Vayne/Xayah). Another one is that against the Jhin who was building crit, you went for Thornmail when in that spot it would have been better to build a Randuins.
Try that and see how you go