Hi.
Some of the below mentioned may help you:
Do you have the latest updates for your email applications and operating system.
Do you have multiple applications managing your email accounts for example using a gmail application and samsung email application which are managing the same email account, if so this could be causing your issues because of backround syncing.
Have you tried going to application settings and checking your application has the relevant permissions. From the same menu you could try force stopping the application and re opening the application.
Have you tried uninstalling and reinstalling your email applications, that can sometimes fix some issues, or alternatively you can delete your email account from your applications then add them again if your application cannot be uninstalled.
Have you tried using a different application to manage your accounts.
Have you tried cleaning and optimising your ram/storage using your device maintenance appication, this sometimes fixes issues.
Have you tried a full shut down.
Not trying to tell you how to suck eggs with some of the above lol.
This may save you time in the future:
I have automatic deleting turned on for my device only which deletes old emails once they are older than a set time period, however deleted emails can still be viewed via online account using a internet browser.
Hope this helps.
