there is no Lineage OS 7 and 9… But as Lineage OS is using the numbering from Cynogenmod there indeed is a CynogenMod 7 and 9.
CM 7 => builds Android 2.3.2 (from beginning of 2011)
CM 9 => builds Android 4.0.1 (from end of 2011)
Don’t you think that’s a bit too outdated to be supported?
Or do you mean LinOS 14 resp. LinOS 16? Would build Android 7 resp. Android 9.
Regardless… it might be due to the compability of LinOS that this fails. But I’m not sure.