The bitwise Stateflow operators (&, |, and ^) should not be used in Stateflow charts unless you want bitwise operations:
To enable bitwise operations,
Select File > Chart Properties.
Select Enable C-bit operations.
Use && and || for Boolean operation.
Use & and | for bit operation.
Use & and | for Boolean operation.
By Task > Modeling Standards for MAAB > Stateflow > Check for bitwise operations in Stateflow charts