Hi,
Please check to use MSCAN_CANIDMRn register (MSCAN Identifier Mask Register n of First Bank).
Such as below picture shows how to set related register to filter extended ID ():
To receive standard identifiers in 32-bit filter mode, it is required to program the last three bits (AM[2:0]) in the mask registers CANIDMR3 to "don't care."

For you want to receive all Extended ID CAN frame, it need to set CANIDMR[0~3] registers all to 0xFF.
Wish it helps.
best regards
Ma Hui
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