RuntimeError: Cannot return the results in a contiguous 2D array. Probably ef or M is too small

[esmailoghli]

This error occurs regardless of how much I increase M and ef.
My index has around 80k elements, so it is not very small so that the requested K vectors are not fetched, and the error only happens when I have deleted some elements in the process, i.e., marked as delete.
However, if I don't delete vectors in the process, the error is never raised.

Anyone has faced this issue with deleting vectors and facing this error?