Trouble getting the fix NPT ensemble to work

I was given this could that was initially fix NVT but I need to change values to where pressure is constant to see volumetric changes. When i run this code I run into an error: ERROR: Must not have multiple fixes change box parameter x (…/domain.cpp:168)
Last command: run 10000
should i add another y parameter for my fix NPT command line?

LAMMPS Input Script for Bulk Water

units metal
newton on
dimension 3
boundary p p p
atom_style full
bond_style harmonic
angle_style harmonic

variable T equal 300.0 # run temperature
variable Tinit equal 320.0 # equilibration temperature
variable V equal vol
variable dt equal 0.001
variable P equal press
variable p equal 20 # correlation length
variable s equal 5 # sample interval
variable d equal $p*$s # dump interval

convert from LAMMPS metal units to SI

variable kB equal 1.3806504e-23 # [J/K] Boltzmann
variable bar2Pa equal 100000.0
variable A2m equal 1.0e-10
variable ps2s equal 1.0e-12
variable convert equal {bar2Pa}*{bar2Pa}{ps2s}*{A2m}{A2m}*{A2m}

setup problem

read_data bulk_water_1.dat
run_style verlet

group wat type 1 2
group oxy type 1

Potential Calculation

pair_style hybrid lj/cut/tip4p/long 1 2 1 1 0.1577 10.0 #lj/cut 10.0 # tersoff
kspace_style pppm/tip4p 1.0e-4

pair_coeff * * tersoff BNC.tersoff NULL NULL

pair_coeff 1 1 lj/cut/tip4p/long 0.009066589 3.1688000
pair_coeff 1 2 lj/cut/tip4p/long 0.0 0.0
pair_coeff 2 2 lj/cut/tip4p/long 0.0 0.0

bond_coeff 1 0 0.9572
angle_coeff 1 0 104.52

neighbor 2.0 bin
neigh_modify every 1 check yes

timestep ${dt}
thermo $d

#----------------------------Energy minimization----------------------------
fix 1 all box/relax iso 1.0 dilate partial

min_style cg ## minimization (using CG method)
minimize 1.0e-10 1.0e-10 1000 1000

unfix 1

#----------------------------System relaxation------------------------------

fix WatShake wat shake 1e-4 20 0 b 1 a 1

timestep 0.5
velocity all create 300.0 54391 mom yes rot yes dist gaussian #temp Tpt bias yes

#fix npt1 wI npt temp $T $T 0.0001 x 1.0 1.0 0.1 y 1.0 1.0 0.1

thermo 1000
thermo_style custom step cpu temp press ke pe etotal vol density #c_TR c_TM
dump 2dump all atom 1000 Trans_NPT_output.lammpstrj
run 20000

unfix npt1

undump 2dump

group WG type 1 2 3
fix WatShake wat shake 1e-4 20 0 b 1 a 1

#-----------------------equilibration and thermalization----------------------

velocity all create {Tinit} 102486 mom yes rot yes dist gaussian fix NPT all npt temp {Tinit} ${Tinit} 100 x 1.0 1.0 1000.0
run 20000

#----------------------viscosity calculation, switch to NVE if desired----------

velocity all create $T 102486 mom yes rot yes dist gaussian
fix NPT all npt temp $T $T 100 x 1.0 1.0 1000.0
#unfix NVT
#fix NVE all nve

reset_timestep 0
variable pxy equal pxy
variable pxz equal pxz
variable pyz equal pyz
fix SS all ave/correlate $s $p d & v_pxy v_pxz v_pyz type auto file S0S2t.dat ave running variable scale equal {convert}/(${kB}$T)$V*s*{dt}
variable v11 equal trap(f_SS[3]){scale} variable v22 equal trap(f_SS[4])*{scale}
variable v33 equal trap(f_SS[5])
${scale}
thermo_style custom step temp press v_pxy v_pxz v_pyz v_v11 v_v22 v_v33

restart 1000000 Water_GF_NVT.restart

run 5000000
variable v equal (v_v11+v_v22+v_v33)/3.0
variable ndens equal count(all)/vol
print “average viscosity: $v [Pa.s] @ T K, {ndens} atoms/A^3”

Your post is not very readable (can you read it well?) because you don’t follow what is explained in the “Guidelines” post about how to correct format quoted text (There is a reason why it has “Please Read This First” in the title).

From what I can see, this input cannot generate the error that you are quoting.
Besides, the error message explains clearly what is wrong.