The value of cross-section for NLO is very High as compared to LO cross-section

I am trying to calculate cross-section for (NLO) the process p p > z b [QCD]
but the value of cross-section i got is very high ( 872.5 ± 27 pb)
With LO calculation of same process i got correct value (p p > z b , z > mu+ mu-) which is 10.9 +-0.003 +-0.23 pb
relative paper is this https://arxiv.org/pdf/2003.11960.pdf
Cards information is
<LesHouchesEvents version="3.0">
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## PARAM_CARD AUTOMATICALY GENERATED BY MG5 FOLLOWING UFO MODEL ####
######################################################################
## ##
## Width set on Auto will be computed following the information ##
## present in the decay.py files of the model. ##
## See arXiv:1402.1178 for more details. ##
## ##
######################################################################

###################################
## INFORMATION FOR MASS
###################################
Block mass
    6 1.730000e+02 # MT
   15 1.777000e+00 # MTA
   23 9.118800e+01 # MZ
   25 1.250000e+02 # MH
## Dependent parameters, given by model restrictions.
## Those values should be edited following the
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## but they are important for interfacing the output of MG5
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  2 0.000000e+00 # u : 0.0
  3 0.000000e+00 # s : 0.0
  4 0.000000e+00 # c : 0.0
  5 0.000000e+00 # b : 0.0
  11 0.000000e+00 # e- : 0.0
  12 0.000000e+00 # ve : 0.0
  13 0.000000e+00 # mu- : 0.0
  14 0.000000e+00 # vm : 0.0
  16 0.000000e+00 # vt : 0.0
  21 0.000000e+00 # g : 0.0
  22 0.000000e+00 # a : 0.0
  24 8.041900e+01 # w+ : cmath.sqrt(MZ__exp__2/2. + cmath.sqrt(MZ__exp__4/4. - (aEW*cmath.pi*MZ__exp__2)/(Gf*sqrt__2)))

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Block sminputs
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## INFORMATION FOR YUKAWA
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Block yukawa
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   15 1.777000e+00 # ymtau

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## INFORMATION FOR DECAY
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DECAY 6 1.491500e+00 # WT
DECAY 23 2.441404e+00 # WZ
DECAY 24 2.047600e+00 # WW
DECAY 25 6.382339e-03 # WH
## Dependent parameters, given by model restrictions.
## Those values should be edited following the
## analytical expression. MG5 ignores those values
## but they are important for interfacing the output of MG5
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DECAY 13 0.000000e+00 # mu- : 0.0
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DECAY 15 0.000000e+00 # ta- : 0.0
DECAY 16 0.000000e+00 # vt : 0.0
DECAY 21 0.000000e+00 # g : 0.0
DECAY 22 0.000000e+00 # a : 0.0
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# QUANTUM NUMBERS OF NEW STATE(S) (NON SM PDG CODE)
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        2 1 # number of spin states (2S+1)
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# *
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# *
# mind the format: variable = value # comment *
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#***********************************************************************
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