Sync not possible

I’ve installed the wordpress app on my iphone, but am not able to post new blogs. The error message is:
The Jetpack site is inaccessible or returned an error: transport eror – HTTP status code was not 200 (503) [-32300]

I don’t know how to fix it and would appreciate every comment on this. Thanks in advance.

dageri

https://wordpress.org/plugins/jetpack/