Error at Joint probable cause Negative diagonal

Good day all.

I'm having trouble proceeding with my analysis of a particular structure. STAAD keeps giving me this error.

***ERROR - AT JOINT 34 DIRECTION = MY
PROBABLE CAUSE NEGATIVE DIAGONAL =>LDLT MTX
K-MATRIX DIAG= 1.8446785E-02 L-MATRIX DIAG= -3.4622283E-07 EQN NO 299

I'm currently running version 20.07.11.50 of the software.

Here is the input.

STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 14-Jul-16
END JOB INFORMATION
INPUT WIDTH 79
UNIT MMS KN
JOINT COORDINATES
1 0 0 0; 2 0 2284 0; 3 0 2284 200; 4 -200 2284 200; 5 200 2284 200;
6 -200 2284 -200; 7 200 2284 -200; 8 -154.776 2284 200; 9 154.766 2284 200;
10 -154.776 2284 -200; 11 154.766 2284 -200; 12 -154.776 2334.8 200;
13 154.766 2334.8 200; 14 -154.776 2334.8 -200; 15 154.766 2334.8 -200;
16 -154.776 2334.8 400; 17 154.766 2334.8 400; 18 -154.776 2334.8 -400;
19 154.766 2334.8 -400; 20 -154.776 2334.8 320; 21 154.776 2334.8 320;
22 -154.776 2334.8 -320; 23 154.776 2334.8 -320; 24 -154.776 2436.4 320;
25 154.776 2436.4 320; 26 -154.776 2436.4 -320; 27 154.776 2436.4 -320;
28 3100 0 0; 29 3100 2284 0; 30 3100 2284 200; 31 2945.22 2284 200;
32 3254.77 2284 200; 33 2945.22 2284 -200; 34 3254.77 2284 -200;
35 2945.22 2334.8 200; 36 3254.77 2334.8 200; 37 2945.22 2334.8 -200;
38 3254.77 2334.8 -200; 39 2945.22 2334.8 400; 40 3254.77 2334.8 400;
41 2945.22 2334.8 -400; 42 3254.77 2334.8 -400; 43 2945.22 2334.8 320;
44 3254.78 2334.8 320; 45 2945.22 2334.8 -320; 46 3254.78 2334.8 -320;
47 2945.22 2436.4 320; 48 3254.78 2436.4 320; 49 2945.22 2436.4 -320;
50 3254.78 2436.4 -320; 51 2900 2284 200; 52 3300 2284 200; 53 2900 2284 -200;
54 3300 2284 -200; 55 -570 2436.4 320; 56 -570 2436.4 -320; 57 3670 2436.4 320;
58 3670 2436.4 -320;
MEMBER INCIDENCES
1 1 2; 4 8 12; 5 9 13; 6 10 14; 7 11 15; 8 18 22; 9 22 14; 10 14 12; 11 12 20;
12 20 16; 13 19 23; 14 23 15; 15 15 13; 16 13 21; 17 21 17; 18 20 24; 19 21 25;
20 23 27; 21 22 26; 22 28 29; 23 29 30; 24 31 35; 25 32 36; 26 33 37; 27 34 38;
28 41 45; 29 45 37; 30 37 35; 31 35 43; 32 43 39; 33 42 46; 34 46 38; 35 38 36;
36 36 44; 37 44 40; 38 43 47; 39 44 48; 40 46 50; 41 45 49; 43 55 24; 44 24 25;
45 25 47; 46 47 48; 47 48 57; 48 56 26; 49 26 27; 50 27 49; 51 49 50; 52 50 58;
53 2 3; 54 29 30;
ELEMENT INCIDENCES SHELL
3 6 4 5 7; 42 53 51 52 54;
ELEMENT PROPERTY
3 42 THICKNESS 8
DEFINE MATERIAL START
ISOTROPIC STEEL
E 205
POISSON 0.3
DENSITY 7.68195e-008
ALPHA 1.2e-005
DAMP 0.03
TYPE STEEL
STRENGTH FY 0.2532 FU 0.4078 RY 1.5 RT 1.2
ISOTROPIC CONCRETE
E 21.7185
POISSON 0.17
DENSITY 2.35616e-008
ALPHA 1e-005
DAMP 0.05
TYPE CONCRETE
STRENGTH FCU 0.027579
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
1 22 TABLE ST W10X26
8 TO 17 28 TO 37 43 TO 52 TABLE ST C4X7
MEMBER PROPERTY
4 TO 7 18 TO 21 23 TO 27 38 TO 41 53 54 PRIS YD 3 ZD 3
CONSTANTS
MATERIAL STEEL MEMB 1 3 8 TO 17 22 28 TO 37 42 TO 52
MATERIAL CONCRETE MEMB 4 TO 7 18 TO 21 23 TO 27 38 TO 41 53 54
SUPPORTS
1 28 FIXED
MEMBER RELEASE
DEFINE WIND LOAD
TYPE 1 WIND 1
<! STAAD PRO GENERATED DATA DO NOT MODIFY !!!
ASCE-7-2010:PARAMS 200.000 KMPH 4 2 1 0 0.000 FT 0.000 FT 0.000 FT 1 -
0 40.000 FT 25.000 FT 0.500 FT 0.600 2.000 0.010 -
0 0 0 0 1.044 1.000 1.000 0.850 0 -
0 0 0 0.879 1.600 -0.550
!> END GENERATED DATA BLOCK
INT 1.92027e-006 1.92027e-006 1.96966e-006 2.0148e-006 2.05644e-006 -
2.09514e-006 2.13133e-006 2.16535e-006 2.19748e-006 2.22793e-006 2.2569e-006 -
2.28454e-006 2.31098e-006 2.33634e-006 2.3607e-006 HEIG 0 4572 5158.15 -
5744.31 6330.46 6916.62 7502.77 8088.92 8675.08 9261.23 9847.38 -
10433.5 11019.7 11605.8 12192
EXP 1 JOINT 1 TO 58
DEFINE UBC ACCIDENTAL LOAD
ZONE 0.04 I 1 RWX 4.5 RWZ 4.5 STYP 1 NA 1.1 NV 1.4
SELFWEIGHT 1
MEMBER WEIGHT
43 48 CON 6.8 120
45 50 CON 6.8 1395.22
47 52 CON 6.8 295.224
LOAD 1 LOADTYPE Seismic TITLE EQX
UBC LOAD X 1
PERFORM ANALYSIS
CHANGE
LOAD 2 LOADTYPE Seismic TITLE EQZ
UBC LOAD Z 1
PERFORM ANALYSIS
CHANGE
LOAD 3 LOADTYPE Dead TITLE DEAD LOAD
SELFWEIGHT Y -1
MEMBER LOAD
43 48 CON GY -6.8 120
45 50 CON GY -6.8 1395.22
47 52 CON GY -6.8 295.224
CALCULATE RAYLEIGH FREQUENCY
LOAD 4 LOADTYPE Live REDUCIBLE TITLE LIVE LOAD
LOAD 5 LOADTYPE Wind TITLE WIND LOAD
WIND LOAD X 1 TYPE 1 OPEN
WIND LOAD Z 1 TYPE 1 OPEN
LOAD 6 LOADTYPE None TITLE MODAL CALCULATION
SELFWEIGHT X 1 LIST ALL
SELFWEIGHT Y 1 LIST ALL
SELFWEIGHT Z 1 LIST ALL
MODAL CALCULATION REQUESTED
LOAD COMB 7 COMBINATION LOAD CASE 7
3 1.4
LOAD COMB 8 COMBINATION LOAD CASE 8
3 1.2 4 1.4
LOAD COMB 9 COMBINATION LOAD CASE 9
3 1.2 5 0.8
LOAD COMB 10 COMBINATION LOAD CASE 10
1 1.0 3 1.2 4 0.5
LOAD COMB 11 COMBINATION LOAD CASE 11
2 1.0 3 1.2 4 0.5
LOAD COMB 12 COMBINATION LOAD CASE 12
1 1.0 3 0.9
LOAD COMB 13 COMBINATION LOAD CASE 13
2 1.0 3 0.9
PERFORM ANALYSIS
PARAMETER 1
CODE LRFD
DFF 360 MEMB 1 22
PERFORM ANALYSIS
GROUP MEMB 1 22
GROUP MEMB 6 8 TO 17 28 TO 37
GROUP MEMB 43 TO 52
PARAMETER 3
CODE LRFD
STEEL MEMBER TAKE OFF LIST 1 22
CHECK CODE MEMB 1 22
FINISH

I thank you all for any assistance you may provide. All the best.