I just completed landing on the Mun and then my fuel glitched (another issued I'll describe below later), so I loaded a quick save.
Upon load however, my vessel had no orbital lines and I could not get them back by re-loading or by going to the tracking station and back.
This is a major issue, especially for a space game
I took more screenshots but these show it off best. You can find my Steam Screenshots for KSP2 here:
https://steamcommunity.com/id/Tazooka/screenshots/?appid=954850
In the end I had to recover my vessel as it randomly broke from the Kraken near Kerbin:
You can see what happens here with this video in the same mission:
Link to Reddit video on r/KerbalSpaceProgram
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As mentioned earlier, there is a fuel glitch and it keeps happening to me on most vessels.
Basically fuel from upper stages is being used for lower stages even when there are no fuel lines and crossfeed is disabled. I have to keep using the recourse manager to keep refilling the upper stage tanks that keep being emptied
Its like the struts are being used as fuel lines....