Why does the metronome reset when changing the beat?

Hello.

I’m trying to change the original 4/4 time signature to 2/4 at a certain metronome position, but when it reaches 1 1,000 it resets to 1 1,000

I want it to continue where it’s going.
That is, if I make the change at 6 1,000, then it should do 6 1,000 - 6 2,000, 7 1000 - 7 2000, etc.

Thanks

Any idea?