Sorry, but the tip is obvious (and one I am very close to following myself)
“Take another long break”
If you really want to use MSFS202 and simbrief Flight Plans, the developer of LNM has a work around, because LNM can produce more MSFS2020 compatible Flight Plans than simbrief.
Load your simbrief generated FP into LNM , and then export it in MSFS format and use that exported plan.