I’ve just re-queued your picture for plate solving, but if it fails again I’m afraid there’s not much I can do as Telescopius actually uses Astrometry.net service to plate solve.
Weird thing is some pictures are plate solved correctly on astrometry.net but not when using their service through the API. I believe they use different index files, but the reason remains unknown to me.
This image is indeed correctly solved on astrometry.net. I also tried a script I use on Pixinsight to blindsolve images with astrometry.net and that also succeeded.
It’s not a big deal anyway, but I thought I’d let you know.