Locked in too late, what should i do?

Decided to lock in mid way through the year with near failing grades, had time to save only 2 A levels out of the 3, being Maths and Computer Science, both near or at A*. 3rd Subject being Accounting completely was left untouched, probably at U-E level. I was originally planning to retake only accounting in m/j 2027. Since i will try to apply for international unis (mainly Germany), i don't know if the 2 A levels from the past sitting and the second one will count as 3 a levels. Do they accept cumulative sittings? Or am i just left with retaking all 3 next sitting?