Updated (05/2023)
There are some tips in the comments and I brought them to update this question. If you're facing this problem, then you are probably using a Linux distro and your project is hitting your system's file watchers limit.
Check your current inotify file watch limit by executing:
$ cat /proc/sys/fs/inotify/max_user_watches
You can set a new limit temporarily with:
$ sudo sysctl fs.inotify.max_user_watches=131070
$ sudo sysctl -p
Or you can set a permanent limit:
echo fs.inotify.max_user_watches= 131070 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p
Here we are setting 131070 file limit (as suggested by @Dmitriy in the comments). If this limit doesn't works for your system you can twice this number.
This documentation provides more technical details.
Old answer
If you are using Linux, your project is hitting your system's file watchers limit
To fix this, on your terminal, try:
echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p
node_modules
are essential because all the packages are there. I've tried to kill the previous processes running on the port of my server, it worked for me but I don't know how long it will take now :D – Epilimnion