GFCI receptacles are extremely sensitive, there are any number of reasons this may not be working for you. The first thing you can do is to make sure that the wire feeding your 2 other outlets off of the outside GFCI are connected to the line side of the device. There are 2 sides to any GFCI: the "line" and the "load" side. The line connections are typically at the bottom, and the load at the top.
The load side is protecting all the downstream receptacles on the circuit. Be sure you have the blacks ("hot" or "line") and whites (neutrals) all on the correct side. Any receptacles downstream don't need to be GFCIs because they will automatically be protected if connected to the load side of the first GFCI.
If you want to use GFCIS for the two new receptacles then you should make sure they are both connected to the line side BEFORE the outside GFCI so they will work independently of the outside one.
As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.
Before you do any work yourself,
on electrical circuits, equipment or appliances,
always use a test meter to ensure the circuit is, in fact, de-energized.
IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB
SAFELY AND COMPETENTLY
REFER THIS WORK TO QUALIFIED PROFESSIONALS.