Tempreture keeps 0 in NVT simulation

Dear LAMMPS users:
I got a problem in simulation when I tried to deposit benzene molecules into the system. I set an NVT ensemble in input file but somehow, the output tempreture keeps 0.

Here is my input file:

# basic settings
units			metal
dimension		3
processors		* * *
boundary		f f f
box 			tilt large
atom_style		full
region 			box block -50 50 -50 50 -50 50
create_box 		2 box
mass 			1 12.011
mass 			2 1.008

# Wall
fix 			xwalls_out all wall/reflect xlo EDGE xhi EDGE
fix 			ywalls_out all wall/reflect ylo EDGE yhi EDGE
fix 			zwalls_out all wall/reflect zlo EDGE zhi EDGE

# potential
pair_style 		airebo 3.0 1 1
pair_coeff 		* * CH.airebo C H

# md parameters
neighbor		4 bin
neigh_modify		every 5 delay 0 check yes	

# outputs
thermo			5000
thermo_style		custom step atoms temp pe press cpu cpuremain
dump			dump_traj all custom 5000 md.lammpstrj id type x y z



reset_timestep 		0

fix			simu all nvt temp 1300 1300 10

molecule 		benzene benzene.txt
region			depo block -20 20 -20 20 -20 20 side in
fix			d all deposit 5000 0 10000 43 region depo near 2 mol benzene vz 1 2 target 0 0 0 units box

timestep		0.0002     #0.2fs	
run			50000000
unfix			simu

And the logfile shows:

   Step        Atoms         Temp          PotEng         Press           CPU          CPULeft    
         0           0   0              0              0              0              0            
      5000          12   0             -59.073352     -0.74439682     0.27472156     2746.9468    
     10000          12   0             -59.004881      5.3254511      0.56150226     2806.9521    
     15000          24   0             -118.14698     -0.071749304    0.84290607     2808.8458    
     20000          24   0             -118.00889      0.046536485    1.1138145      2783.4234    
     25000          36   0             -177.2865      -1.8469684      1.512384       3023.2566    
     30000          36   0             -177.13925      0.74475364     1.9307181      3215.9335    
     35000          48   0             -236.24362     -4.060242       2.3557171      3362.955     
     40000          48   0             -236.1825       13.176399      2.7737643      3464.4323    
     45000          60   0             -295.36735      1.3508792      3.2273596      3582.7282    
     50000          60   0             -295.21711     -5.8647913      3.6706351      3666.9649    
     55000          72   0             -354.40909     -2.9354915      4.1816608      3797.3285    
     60000          72   0             -354.28926      9.125796       4.6639636      3881.9727    
     65000          84   0             -413.64709     -0.6177212      5.1679972      3970.2147    
     70000          84   0             -413.34639      0.92806171     5.7181491      4078.6743    
     75000          96   0             -472.60259      1.9928655      6.382392       4248.5459    
     80000          96   0             -472.37943      1.0111304      7.0506765      4399.6224    
     85000         108   0             -531.73644     -0.63309383     7.7872078      4572.9235    
     90000         108   0             -531.55459      1.5200635      8.6422831      4792.6263    
     95000         120   0             -590.77964      2.0071844      9.3749053      4924.786     
    100000         120   0             -590.62637      2.5453963      9.976851       4978.4489    
    105000         132   0             -649.97228      5.1530832      10.5837        5029.2738    
    110000         132   0             -649.83864     -2.2404826      11.353826      5149.4763    
    115000         144   0             -708.96412     -2.8182925      12.116448      5255.9048    
    120000         144   0             -708.86216     -2.100324       12.931084      5375.0206    
    125000         156   0             -768.33642      7.8596472      13.802127      5507.0489    
    130000         156   0             -768.04664      4.775277       14.661123      5624.2327    
    135000         168   0             -827.21758     -5.4743706      15.612507      5766.7978    
    140000         168   0             -827.22699      8.0657835      16.621306      5919.5595    
    145000         180   0             -886.57953     -4.5827629      17.789945      6116.6746    
    150000         180   0             -886.46277     -1.5328398      19.08484       6342.5289    
    155000         192   0             -945.75208     -8.6983904      20.31692       6533.5283    
    160000         192   0             -945.59815      15.328054      21.686467      6755.3345    
    165000         204   0             -1004.8316     -7.6975812      23.033807      6956.9078    
    170000         204   0             -1004.6918      7.112433       24.267679      7113.285     
    175000         216   0             -1063.9447     -4.6912574      25.591739      7286.3337    
    180000         216   0             -1063.9328     -8.9323971      26.945383      7457.8833    
    185000         228   0             -1123.0004     -0.37446627     28.64733       7713.8744    
    190000         228   0             -1123.0226      5.4853146      30.485262      7991.9523    
    195000         240   0             -1182.209      -12.216522      32.294614      8248.3758    
    200000         240   0             -1182.1335     -2.3325516      34.410162      8568.1304    

I suppose there’s something wrong with my input and hope to get advice about that.

Since the system has variable number of atoms, one would typically use dynamic/dof for temperature calculation:

compute mytemp all temp
compute_modify mytemp dynamic/dof yes
fix simu all nvt temp 1300 1300 10
fix_modify simu temp mytemp

and set thermo_modify temp mytemp to get correct temperature in thermo outputs.
See compute_modify command — LAMMPS documentation

I get it, thank you for your kind suggestion.