Have you read the manual or watched rigging / sailing instructional video?
You need to tack and place each foil on the lee side to lock them one at a time.
Quote:
Deploying the Foils
To lock a foil down it is necessary that the foil
being locked is on the leeward side of the
boat. If the foil is on the weather side of the
boat, water pressure will prevent the foil from
coming down all the way and locking. When
the foil is on the leeward side, the water pressure
will push the foil down and in. It might be
necessary to sail on both tacks to get both foils
locked down. If the boat is in irons, it is possible
to simply push the sail link from side to
side, which will move the boat side to side and
lock both foils down.
If you release the line and the foil does not
go down, see if it is cleated in the cleat on the
beam. If it is, pull on the line to un-cleat it. If
the line still does not go out, try releasing the
sensor retraction line. If the lines are twisted in
the beam, tension on the sensor retraction line
can cause too much friction on the foil retraction
line.