Usually the prompt for web push notifications is displayed only once, the first time that the user visits a website. What if the user blocks the notifications? Is there a way to show the notifications prompt when the user visits the website again?
When the user blocks the notifications you cannot display the browser prompt again, due to browser restrictions... however there are some alternative solutions.
For example, you can display a custom prompt (using HTML / CSS) as many times as you want, and then display the browser prompt only if the user says yes to your custom prompt.
Otherwise you can display a message only to users who have blocked the notifications, asking to unblock the notifications. In this case the user will have to open his browser preferences to change the permissions for your website.
Another alternative is to avoid to display the browser prompt immediately, when the user enters your website. Instead you can wait that the user clicks a button to subscribe to your web push notifications. In this case the browser prompt will be displayed only after the click on the "Subscribe" button and it is very likely that the user will accept to receive the notifications.