I am trying to test if the sum of coefficients is significantly different from 0, but for some reason I keep getting the error "r(303) equation not found"

What am I doing wrong here?

Code:
   regress long_short_return msciworld_excess_return d_e3_1 d_e10_1 d_e13_1 d_e15_1 d_e18_1 d_e19_1 //COPY PASTE HERE THE SELECTED EVENT DUMMIES
hettest 
vif
   estimates store long_short1

   test ([long_short1]d_e3_1+[long_short1]d_e10_1+[long_short1]d_e13_1+[long_short1]d_e15_1+[long_short1]d_e18_1+[long_short1]d_e19_1) = 0
   
   regress long_short_return msciworld_excess_return d_e3_3 d_e10_3 d_e13_3 d_e15_3 d_e18_3 d_e19_3 //COPY PASTE HERE THE SELECTED EVENT DUMMIES
hettest 
vif   
   estimates store long_short3
    test ([long_short3]d_e3_3+[long_short3]d_e10_3+[long_short3]d_e13_3+[long_short3]d_e15_3+[long_short3]d_e18_3+[long_short3]d_e19_3) = 0
   
   regress long_short_return msciworld_excess_return d_e3_5 d_e10_5 d_e13_5 d_e15_5 d_e18_5 d_e19_5 //COPY PASTE HERE THE SELECTED EVENT DUMMIES
hettest 
vif   
   estimates store long_short5
   
 
  test ([long_short5]d_e3_5+[long_short5]d_e10_5+[long_short5]d_e13_5+[long_short5]d_e15_5+[long_short5]d_e18_5+[long_short5]d_e19_5) = 0