We are accustomed to the child asking why we dip twice on Seder night, but we need to look at this from a deeper perspective.
Rabbeinu Monoach on the Rambam in Hilchos Chometz uMatzoh, compares the word Karpas to the word Pasim, which alludes to the beautiful coat of Yosef that was taken from him when he was sold to Mitzrayim.
As an aside, we know that the Gematriyo of the word Pasim is 190, which outlines how much pain Yosef suffered which eventually relieved us of the 190 years in mitzrayim.
The shevotim took off his coat and dipped it jnto the blood of a goat … an act of undefined and unimaginable separation. Brothers acting as unbrotherly as possible
This was remedied on Seder night in mitzrayim while eating the Morning Pesach in families and groups of friends and they dipped the hyssop grass into the blood and smeared it onto their door posts
We dip twice to remind ourselves of how we got ourselves into the exiles of mitzrayim and how we left our troubles behind.
In one word. Achdus.
We left mitzrayim when they were acting as one family
That is why we dip our food twice on Seder night