Great app, but emails are stuck in Outbox!

I really like this app with all its features like Touch ID protected emails, and its nice simple UI but every time I send an email, it gets stuck in my outbox. This really disappoints me and if it was fixed, I would give this review 5 stars. Overall though, if it functioned correctly for me, GREAT app!

GroovyWolf Apple about Email - Edison Mail, v1.4.1