Why does 'on experience spawn' work before 'on fishing'?

[Gravity_Fall]

on fishing:
    send "on fishing" to console

on exp spawn:
    set {_exp} to "%spawned exp%"
    {_exp} is not "0 xp"
    send "%{_exp}%" to console
 
on item spawn:
    send "on item spawn" to console

[00:57:45 INFO]: on fishing <- throw
[00:57:53 INFO]: on fishing       <- bite
[00:57:54 INFO]: 3 xp             <- catch (on exp spawn) - Why does it work first?
[00:57:54 INFO]: on fishing       <- catch (on fishing)
[00:57:54 INFO]: on item spawn    <- catch (on item spawn)

I am going to make a mini game using three kinds of events. But the 'on exp spawn' event works before 'on fishing'.
How can I adjust the priority of an event?

If I cancel an event while it's a catch, I don't drop the experience, but the 'on exp spawn' event shows the experience value.