When you cannot receive the emails on the yahoo account and it keeps showing imap related error. it means, there is a problem with the account configuration. probably, the account is not properly configured or something is wrong with the mail settings. so here are the things to change.
1. First of all, you need to check the imap server settings. make sure these settings are correct. the incoming server address should be imap.mail.yahoo.com
2. Check the port no and encryption type for the yahoo account. you need to enter 993 and SSL.
3.When you can't reeive the emails on the yahoo mail. you should check the internet settings. most probably, something is wrong with the user account. so delete all these settings and then update them.
4. Uninstall the current email account from the iphone and then re-add them using the valid mail settings.
So these are the steps to fix the yahoo mail imap server problems. in case, if you are dealing with the printer issues. please visit askprob blogs for more help.
