No forces on STL_Type_fuse (fuselage)

Hi I have imported a different vertical tail design as an stl/fuselage to the software along with the defined flying wing I made in the software. Reading the data, I saw that the tail I imported has no Fx, Fy, Fz (=0). Why is it? and how can I workaround with this? I have already checked to include the pressure forces. Below is the data copy pasted. Thanks

Type 2 (Fixed lift)
Triangles – Uniform doublet density
Mass = 2.000 kg
CoG_x = 288.012 mm
CoG_z = 3.645 mm
V∞ = 15.377 m/s
α = 10.000°
CP = (335; 3.33e-05; 12.4) mm
CL = 0.5862444
CD = 0.0419211
VCD = 0.0101872
ICD = 0.0317339
CY = 0.0000000
Cl = 0.0000006
Cm = -0.0804771
Cmi = -0.0802335
Cmv = -0.0002436
Cn = 0.0000214
Cni = 0.0000214
Cnv = -0.0000000
Total force, body axes:
Fx= -2.03 N Mx =-9.41e-05 N.m
Fy= 4.52e-07 N My = -0.936 N.m
Fz= 19.6 N Mz = 0.000637 N.m
Forces on parts, body axes:
Main Wing:
Fx= -2.03 N Mx = 7.37e-07 N.m
Fy= 4.52e-07 N My = -0.934 N.m
Fz= 19.6 N Mz =-1.44e-07 N.m
STL_type_fuse_1:
Fx= 0 N Mx =-9.48e-05 N.m
Fy= 0 N My = -0.00115 N.m
Fz= 0 N Mz = 0.000637 N.m