This appears to be an MAPDL GUI bug.
The TBOPT field is not used for the ANISO material option.
As a workaround, try defining your material directly with commands as follows:
*************
MP,EX,1,39600
MP,EY,1,3065.9
MP,EZ,1,3065.9
MP,PRXY,1,0.2
MP,PRYZ,1,0.3
MP,PRXZ,1,0.2
MP,GXY,1,2075.1
MP,GYZ,1,1179.2
MP,GXZ,1,2075.1
!
TB,ANISO,1
TBDATA,1,643.5,8.860588,8.860588,0,0,0
TBDATA,7,13.2,13.2,13.2,0,0,0
TBDATA,13,6.93,6.93,6.93,0,0,0
**********
After you define the materials just use MPLIST and TBLIST commands to check your inputs.
Don't use the MAPDL GUI for this material combination.
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