Same issue. Margin requirements are changing every alternate day.
Reduce margins on one day to free up available margins and let a user take trades. Increase it the next day and make money squaring off positions/ earn delayed payment charges. Rinse and repeat. Happened a third time with me. +1L to -7L overnight. No matter which logic the exchanges/ CC are using, I don’t understand how it is changing every alternate day.
This week’s sequence for me (Eod-Bod):
Mon-Tue: +5L to -8L
Tue-Wed: +1L to +11L
Wed-Thu: +2L to -11L
Thu-Fri: weekly positions expired, so margins freed
Fri-Sat: +1L to -7L