vim or neovim? what terminal emulator are you using? post your nvim init.lua file. try putting both of these in tmux.conf:
set -g default-terminal “xterm-256color”
set-option -ga terminal-overrides “,xterm-256color:Tc”
This is for alacritty terminal emulator + tmux + neovim but may help put you on the right track with whatever te u might be using:
Jared Kushner, Trump’s son-in-law, praises ‘very valuable’ potential of Gaza’s ‘waterfront property’