Scenario tags in Behave sometimes ignore the equal sign

after re-install the whole system now I have to face another problem: Scenario tags in Behave sometimes ignore the equal sign. Sample of my tag that I am using for my project "@case_id=123456"

And here is the problem!

• Case 1: Running whole feature file -> OK

• Case 2: Running only one scenario tags with "=" sign -> 50/50 this tag can run

• Case 3: Running above scenario tags without "=" sign -> OK

Any idea?