pEp always complain wrong passphrase

I have the IMAP and SMTP servers with custom ports for SSL connection, 30001 for IMAP and 30002 for SMTP for example.

I setup my account in pEp successfully and able to receive mails initially.

But it always show a dialog box to complain that I have wrong passphrase and request me to enter my passphrase when I open pEp after the initial setup.

I did enter the correct passphrase in the dialog box but it always pop out the dialog box again and again.

I guess this is a bug. Or does anyone has ideas how to avoid this problem?

Both receiving and sending are worked fine at the initial setup. Because I received the mails and sent a mail out successfully. But pEp complain the passphrase when I open pEp later.

My IMAP is dovecot and the SMTP is postfix. The passphrase is numbers and letters.