API - Export games of a user - inccorrect response

I get invalid results if I try to filter for specific variant like blitz or rapid. Only bullet works.
I used Postman.

For example, searching all games in bullet from Jan 10, 2020 gives me correct result:
GET lichess.org/api/games/user/Terinieks?since=1578607200000&perfType=bullet
2739 games

but: GET lichess.org/api/games/user/Terinieks?since=1578607200000&perfType=blitz
18 games (correct is 166 games)

Rapid also gives incorrect result.
Also tried query other profiles than mine, it seems API is not returning correct results.

Can someone confirm API is not working correctly?! Or am I missing something?