SACS PSI program

I am trying to use SACS PSI program for a single pile but i kept getting error so I started useding problem 2 of SACS manual as input but get totally different result & a singularity in matrix & warning despite manual out put does not indicate the program gives any of these errors. This is the input file and I get this error 

 ** WARNING - SOIL SOL1 CONTAINS STRATA FOR WHICH API RP2A-WSD 21 Supp. 3 RECOMMENDS THE USE OF CPT-BASED METHODS

also this error 

JOINT 101 AT DOF DX
*** ERROR-STIFFNESS MATRIX IS SINGULAR

INPUT FILE IS AS FOLLOW :

PLOPT ENUC
PLTRQ SD
PLGRUP
PLGRUP PL1 28.0 1.00 50.0 50.0
PLGRUP PL1 28.0 0.75 36.0 175.0
PILE
PILE 2 201 PL1 1.0 1.0 8.0 SOL1
SOIL ICP
SOIL AXIAL HEAD 8 SOL1 ICP
SOIL API AXL SLOC 0.001 20.0 SILT 1.0 50.0
SOIL API AXL SLOC 20.00 60.00 SNSL 1.0 100.0
SOIL API AXL SLOC 160.0 SLSN 1.0 40.0
SOIL API AXL SLOC 200.0 SAND 0.9 80.0
SOIL API AXL SLOC 228.0 CLOC 20.0 50.0
SOIL API AXL SLOC 260.0 CLUC 40.0 70.0
SOIL API AXL SLOC 300.0 CLAY 70.0 90.0
SOIL API AXL SLOC 400.0 ROCK 100.0 200.0 100.0
SOIL TORSION HEAD 1000.0SOL1 Y
SOIL LATERAL HEAD 6 28. SOL1 Y
SOIL API LAT SLOC SILTSA 20. 0.5 50.0 20.0
SOIL API LAT SLOC SNSLCA 20.0 1.0 60.0 60.0
SOIL API LAT SLOC SLSNSA 60.0 1.5 70.0 125.0
SOIL API LAT SLOC SANDSA 120.0 140.0 1.75 80.0 125.0
SOIL API LAT SLOC SANDSA 140.0 2.00 80.0 125.0
SOIL API LAT SLOC CLAYS 200.0 3.00 100.0 0.250 0.001
PLSTUB D1002 2.2802 0.01306 625.4
END

Any suggestion how to resolve this