In the job tab, no histogram appears

Strange.

This offers a way for you to retrieve your histogram but not exactly the solution to your problem. So hopefully it will be useful somehow.

First, note that each job you submitted has a job_ID. You actually can see it on the top left of your screenshot. You can "copy and paste" this JobID into line 6 of the script below

from qiskit import IBMQ
from qiskit.visualization import plot_histogram
%matplotlib inline
provider = IBMQ.load_account()
backend = provider.get_backend('ibmq_santiago')
job = backend.retrieve_job('ENTER JOB_ID HERE')
counts = job.result().get_counts()
plot_histogram(counts, color='black', title="Result")

Executing this script through the Jupyter Notebook provided in Quantum Lab will print out your Histogram. For instance, using a JobID for one of my old job, I printed out the following.

Again, not the exact solution to your question but at least this should provide you a way to retrieve your result, plot it, and not wasting your time having to rerun your experiment to get a new plot.