Hi Bartosz,
Did the STATEV(1) and STATEV(2) have a value at each increment in your subroutine? I did as what you said and added "*FIELD, USER, VARIABLE=2" there:
** STEP: Step-1
**
*Step, name=Step-1, nlgeom=NO
*Heat Transfer, end=PERIOD, deltmx=5.
1., 250., 0.0025, 5.,
**
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