The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  X  1  X  1
 0  X  0  0  0  X  X  X a*X a^3*X  0  X a*X a^6*X  0 a^3*X 2*X  X  X  X  0
 0  0  X  0  0 a^7*X a^6*X a*X 2*X a^7*X  X a^7*X a*X a^2*X a^7*X  0 a^2*X a^3*X a^7*X a^3*X  0
 0  0  0  X  0 a^7*X  X a^2*X a^2*X a^6*X a^3*X a^6*X a^3*X a^5*X a^3*X a*X  0 a^6*X a^5*X 2*X  0
 0  0  0  0  X a^6*X 2*X a^3*X  X  X a*X a*X  X a^2*X a^7*X a*X a*X  0  0 2*X  0

generates a code of length 21 over F9[X]/(X^2) who´s minimum homogenous weight is 126.

Homogenous weight enumerator: w(x)=1x^0+320x^126+1760x^135+3488x^144+5832x^152+6304x^153+93312x^161+12216x^162+373248x^170+16240x^171+13176x^180+5544x^189

The gray image is a linear code over GF(9) with n=189, k=6 and d=126.
This code was found by Heurico 1.16 in 23 seconds.