iOS updates usually don't mess with Siri's basic abilities. But for Siri to really shine, it needs an internet connection for many tasks.
Think of it this way: Siri is super smart, but it also needs information from the web to be truly helpful. Imagine a library with tons of books on all sorts of subjects. Siri can still use its knowledge to answer basic questions you might have, like what the capital of France is, even without the library. But if you ask something that requires more research, like finding the best pizza place nearby or checking the weather this weekend in Paris, Siri needs to access the information online just like you would at the library.
So, if Siri seems a little off its game, check your WiFi or cellular data connection to make sure it's working properly. That should help Siri get back to its super-smart and super-helpful self!
Please refer to the pic below


Probably your device may not be connected to the internet.

Connecting to Wi-Fi is the first part and then getting connected to the Internet is the second
- If you are connected to a Wifi, doesn't necessarily mean you are connected to the internet. If you are not connected to wifi could be a problem with iPhone settings or Router/Modem Settings
- If you are not connected to the internet is the sole issue of Router / Modem Settings. Contact your ISP immediately
Internet Over Wi-FI: Contact your ISP (Internet Service Provider), the agency that provided the Internet Service on your Modem/Router to you
Recommended settings for Wi-Fi routers and access points

For your Internet connection.
- Over Cellular/Mobile: contact your Carrier (Cellular Service Provider). The agency that issued the SIM to you
- Over Wi-Fi: Contact your ISP (Internet Service Provider), the agency that provided the Internet Service on your Modem/Router to you
However --> Connect iPhone to the Internet - Apple Support