Android Open SSTP fails with read: Input/output error

[ednt]

I just installed accel-ppp reduced to sstp.
I can establish a VPN SSTP connection from my Win10, everything is fine.

But If I use Open SSTP Client 1.7.1 on an Android smartphone, it results in:

error: : sstp: read: Input/output error

sstp.c line 1095

Same fault like an older issue.
From the code side it looks that there are no data in the stream for fetching.

Strange.

Any ideas?

Best regards,

Bernd