Why some cells in JupyterLab can't run?

Hi everyone, I have encountered a strange problem about how to run cells in jupyterlab.
I use Notebook in JupyterLab. Everything went well at first, but from the day before yesterday, some cells in one of my files can’t run, no errors were reported. Even if I click the “run the selected cells” or “restart the kernel, and rerun the whole notebook”, none of them can run well, print nothing, just jump to the next cell. But markdown can still run well in my notebook, so I am really confused.
I’ve used Rstudio to test those codes and they can be run. I’ve tried restarting jupyterlab and reopening a notebook, but these codes still couldn’t run. I don’t know what went wrong.
Can anyone help me solve this problem please? Thank you all.

This is what it looks like after I click to run.

ps: I can only insert one picture because I am a new user. The picture I inserted is in R language, and python is also like this, nothing is output, just skip to the next cell

The kernel indicator in the upper right should be empty if your code ran and all is good. Plus it says Initializing down in the lower right. Code isn’t going to be able to be run until that says Idle when you start the notebook and pause. Go here and press launch binder so you can launch a session in your browser where you can observe what the indicators should do. If you want to use an R kernel, go here, launch, and then switch to JupyterLab using this method.
Does anything run now in a new notebook? Like try 2 + 2.

My suspicion is you haven’t gotten whatever is serving your notebooks running and so you cannot communicate with a kernel. You don’t describe where you are using JupyterLab from? A local install? A remote JupyterHub?

Markdown doesn’t run so that being rendered when you type and hit return isn’t relevant to the code part and would be expected to correctly right without the kernel.