ᐅ Damp spot in the basement: transition between waterproof concrete and aerated concrete interior wall

Hello, I need advice on the following issue:
After the screed was applied in the basement, the calcium silicate brick interior wall near the entrance bay, at the junction with the waterproofed (WU) exterior wall, was extremely damp and dried only slowly (over nearly 6 weeks). In the end, only a narrow damp strip close to the floor remained visible. However, our heat pump has now been running in heating mode for a little over a week, and the moisture is still visibly and noticeably present. Is this a defect, or can moisture remain in certain areas for such a long time?

Thanks for your support and best regards, Sven

It can last this long if the area is poorly ventilated.

Corners like these tend to dry very poorly. You could sand them down a bit, because a sintered layer forms there over time, which traps moisture even more. If you sand that off, it will dry faster. Give it a try. Karsten