without more information, the most straightforward way is to disable your plugins one at a time and test if things are working (could go the other direction: start from no plugins, and install them one at a time). do this by commenting/uncommenting lines in your config and rerunning sync/clean/install or whatever with your plugin manager.
ideally youd have some idea about what specifically is breaking for you. since you say completion maybe start with whatever you use for that (cmp, mason setup, coc, deoplete, ycm)?
edit: forgot to say, but if you post your config that could be helpful in case there's an obvious err somewhere. is it all macros that fail or only some with specific motions?