ipad and iPhone x have suddenly become very slow

Hey Anna, this problem could possibly be that your internet has became slower, or you have alot of website data, history and cookies. If it happened on your iPad, it must have synced all your website data and history to your iPhone X. If it is your internet, you could try disconnecting some other people from the internet while your trying to use it, (if you have multiple people in your household) or you can call your ISP and tell them your getting low speeds. If it is your website data, history and cookies, open the settings app, scroll down til you see Safari, click on it and scroll all the way down, check the box where it says, "Block All Cookies" then click "Clear History and Website Data". Hope this helps! 🤗