I have a 840C + 611D card with several axes.The problem axis is C3 ( simodrive card 6SN1118-0DG23-0AA0), milling axis.
The motor encoder is Abs. When I am working and the machine goes in safety stop or power down. One card with absolute encoder lost his position.

I already changed the encoder.

On my screen there are no alarms.

I have no spare card here, but I can buy one.
I am not sure that there is something wrong with the card.
Could it not something with parameters.

On the Siemens site I found the manual below:

Parameters 4100 --> 4176 on the 840C
Parameters: 1316 --> 1322 on the 611D. (where can I find these parameters on the HMI)?