Diluted material transfer in fracture, d operators are not defined properly in the current context

Hello,everyone! Coulud anyone help me with this problem? Comosl is used to calculate the coupling problem of solid mechanical field and material transfer field. When no cracks were added in the material transfer field, it could be solved normally. However, when cracks were added in the mass transfer field, the following errors would occur. "d operators are not defined properly in the current context, please use dtang or average operators and d operators instead.- Expression: D (comp1.c,x) ' - I will apprecaite if anyone could help me with this problem!