Not totally sure but it might be that there is no limit check on the approve call, so even if you would just own 1 FPL you could approve for 10B FPL, might explain the transaction.
And the spender account is from @ICPSwap so maybe they have more insights
Many thanks to @rem.codes and @Manu for their accurate explanation!
Additionally, James @jamesbeadle , I’d like to clarify that users can modify their approval limit in the settings. If they wish to expedite swap transactions, they can set a higher approval limit, allowing them to approval once and avoid repeated approvals for a period of time, thereby enhancing swap speed.
You can see that the transaction type is Approve, not transfer (Swap) or Mint