Lithium problem in Big Bang nucleosynthesis?

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Aidyan
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I frequently read of the problem that the measured primordial abundance of lithium does not match the amount expected by Big Bang nucleosynthesis theory. However, I see also graphs like these which seem to suggest that everything is as expected. Is this a contradiction or am I misreading the data or what? Cant reconcile and compute...

https://wmap.gsfc.nasa.gov/universe/bb_tests_ele.html
Log-log plot of element abundance relative to hydrogen against density of ordinary matter relative to photons, with curves for Helium 4, Deuterium, Helium 3 and Lithium 7, and a red vertical line labelled WMAP Observation.
 
That graph only shows the theoretical prediction of the elemental abundances which would be consistent with WMAP data. But yes, observed lithium abundances are way off and we don't know why.