Solder Fatigue with Blattau method (Difference in CTE): Interfaces not found

Anass_MOSSADAQ

On a PCBA board, we’re running a solder fatigue calculation using the Blattau method on a BGA component, but the solver is not detecting the PCB–Solder and Solder–Package interfaces.

Note: the exact same model works with the Syed method (same PCB/balls/package sets, and the same TIE contacts PCB/Solder and Package/Solder).

Could you guide us on what needs to be adjusted to resolve the issue?

Anass_MOSSADAQ

*** PROGRAM STOPPED: FATAL ERROR(s) ENCOUNTERED.

                    ***** END OF REPORT *****

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NOTE # 1422
There were 1 automatic memory expansion(s).
(The result is not affected by this.)

A fatal error has been detected during input processing:

*** ERROR # 3880 ***
Program cannot find interfaces between solder set and other parts. Check
PCB set and component set are properly defined. If contact is used, make
sure contacts between solder set and other parts are defined.
FATSDR ID = 11421
PCB set ID = 4264
Component set ID = 4265
Solder ball set ID = 4266.