STAAD PRO CONNECT "ERROR IN SELECTION PROCESS"

I am running a STAAD Pro CONNECT design on a 2D truss with a double-pitch top chord. While running a member optimization, I received the following message and I don't know why: "ERROR IN SELECTION PROCESS FOR MEMBER- (member #)". I have run multiple designs with single-pitch top chords using the same parameters; however, I believe it may have something to do with the double-pitch top chord. As I look through the results, one of the iterations changed the numbers of the all top chord members to -1 and changed the profile to "T". Does anyone have any idea as to why this is happening? See below for STAAD input.

STAAD TRUSS
START JOB INFORMATION
JOB NAME XXXX
JOB CLIENT XXXX
JOB NO XXXX
JOB PART XXXX
JOB COMMENT XXXX
ENGINEER NAME XXXX
ENGINEER DATE XXXX
END JOB INFORMATION
INPUT WIDTH 79
UNIT INCHES KIP
JOINT COORDINATES
100 0 0 0;
101 99 0 0;
102 198 0 0;
103 297 0 0;
104 396 0 0;
105 495 0 0;
106 594 0 0;
107 693 0 0;
108 792 0 0;
200 0 84 0;
201 99 85.878 0;
202 198 87.756 0;
203 297 89.634 0;
204 396 91.512 0;
205 495 89.634 0;
206 594 87.756 0;
207 693 85.878 0;
208 792 84 0;
MEMBER INCIDENCES
100 100 101;
101 101 102;
102 102 103;
103 103 104;
104 104 105;
105 105 106;
106 106 107;
107 107 108;
200 200 201;
201 201 202;
202 202 203;
203 203 204;
204 204 205;
205 205 206;
206 206 207;
207 207 208;
300 101 201;
301 102 202;
302 103 203;
303 104 204;
304 105 205;
305 106 206;
306 107 207;
400 101 200;
401 102 201;
402 103 202;
403 104 203;
404 104 205;
405 105 206;
406 106 207;
407 107 208;
UNIT FEET KIP
DEFINE MATERIAL START
ISOTROPIC STEEL
E 4.176e+06
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-06
DAMP 0.03
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
100 TO 107 TABLE ST W8X31
200 TO 207 TABLE T W16X31
300 TO 306 TABLE LD L40406 SP 0.0625
400 TO 407 TABLE LD L40406 SP 0.0625
CONSTANTS
MATERIAL STEEL ALL
SUPPORTS
200 PINNED
100 108 208 FIXED BUT FX MX MY MZ
102 104 106 FIXED BUT FX FY MX MY MZ
201 TO 207 FIXED BUT FX FY MX MY MZ
LOAD 1 LOADTYPE Dead TITLE DEAD LOAD
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY -0.297
100 108 FY -0.1485
*TOP CHORD
201 TO 207 FY -1.848
200 208 FY -0.924
SELFWEIGHT Y -1
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY -0.173
*TOP CHORD
200 TO 207 UNI GY -0.254
LOAD 2 LOADTYPE Live TITLE LIVE LOAD
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY -0.001
100 108 FY -0.001
*TOP CHORD
201 TO 207 FY -0.001
200 208 FY -0.001
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY -0.347
*TOP CHORD
200 TO 207 UNI GY -0.001
LOAD 3 LOADTYPE Roof Live TITLE ROOF LIVE
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY -0.001
100 108 FY -0.001
*TOP CHORD
201 TO 207 FY -2.723
200 208 FY -1.3615
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY -0.001
*TOP CHORD
200 TO 207 UNI GY -0.001
LOAD 4 LOADTYPE Snow TITLE SNOW
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY -0.001
100 108 FY -0.001
*TOP CHORD
201 TO 207 FY -0.001
200 208 FY -0.001
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY -0.001
*TOP CHORD
200 TO 207 UNI GY -0.001
LOAD 5 LOADTYPE Wind TITLE WIND (+X)
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FX 0.001
100 108 FY 0.001
*TOP CHORD
201 TO 207 FX 0.001
200 208 FX 0.001
LOAD 6 LOADTYPE Wind TITLE WIND (-X)
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FX -0.001
100 108 FX -0.001
*TOP CHORD
201 TO 207 FX -0.001
200 208 FX -0.001
LOAD 7 LOADTYPE Wind TITLE WIND (-Y)
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY -0.001
100 108 FY -0.001
*TOP CHORD
201 TO 207 FY -1.089
200 208 FY -0.5445
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY -0.001
*TOP CHORD
200 TO 207 UNI GY -0.001
LOAD 8 LOADTYPE Wind TITLE WIND (+Y)
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY 0.001
100 108 FY 0.001
*TOP CHORD
201 TO 207 FY 4.22
200 208 FY 2.11
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY 0.001
*TOP CHORD
200 TO 207 UNI GY 0.001
LOAD 9 LOADTYPE Seismic-H TITLE SEISMIC (+X)
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FX 0.001
100 108 FY 0.001
*TOP CHORD
201 TO 207 FX 0.001
200 208 FX 0.001
LOAD 10 LOADTYPE Seismic-H TITLE SEISMIC (-X)
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FX -0.001
100 108 FX -0.001
*TOP CHORD
201 TO 207 FX -0.001
200 208 FX -0.001
LOAD 11 LOADTYPE Seismic-V TITLE SEISMIC (-Y)
SELFWEIGHT Y -0.057
JOINT LOAD
*BOTTOM CHORD
101 TO 107 FY -0.001
100 108 FY -0.001
*TOP CHORD
201 TO 207 FY -0.001
200 208 FY -0.001
MEMBER LOAD
*BOTTOM CHORD
100 TO 107 UNI GY -0.009
*TOP CHORD
200 TO 207 UNI GY -0.009
LOAD COMB 12 D
1 1.0
LOAD COMB 13 D + L
1 1.0 2 1.0
LOAD COMB 14 D + LR
1 1.0 3 1.0
LOAD COMB 15 D + S
1 1.0 4 1.0
LOAD COMB 16 D + 0.75L + 0.75LR
1 1.0 2 0.75 3 0.75
LOAD COMB 17 D + 0.75L + 0.75S
1 1.0 2 0.75 4 1.0
LOAD COMB 18 D + 0.6W(+X)
1 1.0 5 0.6 7 0.6
LOAD COMB 19 D + 0.6W(-X)
1 1.0 6 0.6 7 0.6
LOAD COMB 20 D + 0.75L + 0.75[0.6W(+X)] + 0.75LR
1 1.0 2 0.75 5 0.45 7 0.45 3 0.75
LOAD COMB 21 D + 0.75L + 0.75[0.6W(-X)] + 0.75LR
1 1.0 2 0.75 6 0.45 7 0.45 3 0.75
LOAD COMB 22 D + 0.75L + 0.75[0.6W(+X)] + 0.75S
1 1.0 2 0.75 5 0.45 7 0.45 4 1.0
LOAD COMB 23 D + 0.75L + 0.75[0.6W(-X)] + 0.75S
1 1.0 2 0.75 6 0.45 7 0.45 4 1.0
LOAD COMB 24 0.6D + 0.6W(+X)
1 0.6 5 0.6 8 0.6
LOAD COMB 25 0.6D + 0.6W(-X)
1 0.6 6 0.6 8 0.6
LOAD COMB 26 D + 0.7E(+X)
1 1.0 9 0.7 11 0.7
LOAD COMB 27 D + 0.7E(-X)
1 1.0 10 0.7 11 0.7
LOAD COMB 28 D + 0.75[0.7E(+X)] + L + S
1 1.0 9 0.525 11 0.525 2 1.0 4 1.0
LOAD COMB 29 D + 0.75[0.7E(-X)] + L + S
1 1.0 10 0.525 11 0.525 2 1.0 4 1.0
LOAD COMB 30 0.6D - 0.7E(-Y) + 0.7E(+X)
1 0.6 11 -0.7 9 0.7
LOAD COMB 31 0.6D - 0.7E(-Y) + 0.7E(-X)
1 0.6 11 -0.7 10 0.7
PERFORM ANALYSIS
DEFINE ENVELOPE
1 TO 11 ENVELOPE 1 TYPE SERVICEABILITY
12 TO 31 ENVELOPE 2 TYPE STRENGTH
END DEFINE ENVELOPE
LOAD LIST ENV 1 2
PARAMETER 1
CODE AISC UNIFIED 2016
METHOD ASD
BEAM 1 ALL
RATIO 0.9 ALL
FYLD 7200 MEMB 100 TO 107 200 TO 207
FYLD 5184 MEMB 300 TO 306 400 TO 407
LX 16.5 MEMB 100 TO 107
LY 16.5 MEMB 100 TO 107
DFF 414 ALL
DJ1 100 MEMB 100 TO 107
DJ2 108 MEMB 100 TO 107
DJ1 200 MEMB 200 TO 207
DJ2 208 MEMB 200 TO 207
DMIN 0.667 MEMB 100 TO 107
DMIN 1 MEMB 200 TO 207
DMAX 0.875 MEMB 100 TO 107
DMAX 1.75 MEMB 200 TO 207
FIXED GROUP
GROUP MEMB 100 TO 107
GROUP MEMB 200 TO 207
GROUP MEMB 300 301 305 306
GROUP MEMB 400 401 406 407
GROUP MEMB 302 TO 304
GROUP MEMB 402 TO 405
SELECT OPTIMIZED
PERFORM ANALYSIS
PARAMETER 2
BEAM 1 ALL
RATIO 1 ALL
TRACK 1 ALL
CHECK CODE ALL
PRINT SUPPORT REACTION LIST 100 108 200 208
PRINT MEMBER FORCES ALL
FINISH

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