Go into your phone settings Debz57 and hit notifications.. Then scroll down your recent notifications until you see the more function. Press that and it gives you a list of all your apps that have notifications and just toggle off your Gmail app or whatever that you don't want to get notifications off. Hope this works for you?. 👍👍 The first step is to the right below sorry and the second to the left.
Next time you get the notification, swipe right gently and you will see the settings for that app. By selecting that, you can see all the types of alerts that are on for Gmail. Sometimes you might get alerts when it is syncing etc. You can keep only those you want on such as new email.