There are a couple of errors there.
if you’d provided your domain name I could have done extra checks. Without though I can only guess at some things.
The problem of your website showing the wrong cert could be in a couple of places usually.
- You haven’t obtained a new cert.
- You have obtained a new cert, but are not using it.
You can check the cert, to see if it’s been renewed, either on your server or via the cert transparency report ( try https://www.google.com/transparencyreport/https/ct/?hl=en ) to see when the most recent one was obtained.
That will tell you if the error is with 1. or 2. in your case.
The crontab you have should run once per month ( personally I run it daily). You should only need “/letsencrypt-auto --renew” to check and renew all certs that are required. I’d also use one of the --hook options to reload apache if needed ratehr than every time the cron is run.
What version of letsencrypt are you running ? You may want to update to the latests ( now named certbot). You also don’t say if you are running this as a user or root (i.e. if you have the relevant permissions ) since the command looks to be a user ( /home/pi … ) yet reloading apache would typically not be an option for a user.