The multiple entries here will be due to the $S\rightarrow\epsilon$

$First(S) = {a,b}$ - so the respective productions go in those cells.

$Follow(S)$ includes \$, and also Follows of A and B. i.e. $Follow(S) = {$, a, b}$ ,and so $S\rightarrow\epsilon$ goes into all these cells.

With this you can conclude that the cells corresponding to $S, a$ and $S, b$ will have multiple entries.