MDD 2.0 neck drifting back?

Ok, let me clarify. So, I got my mom the MDD 2.0 body, and a DDH-06 head directly from Volks when I went to Japan in December 2024. She recently told me (like literally yesterday) that her head keeps drifting back so she's looking upwards. I took a look at it, and it seems to be sitting properly, and her wig isn't particularly heavy, so I'm not sure why this is happening.

Is this an issue anyone else is having? Do I need to maybe go in and tighten a screw? Or is it a design flaw and I should find a third party neck peg?

For full info: she only realized this as an issue recently because she only really started playing with her around last month, as she was waiting on me to do her faceup, and for her eyes to arrive, since I didn't get any while in Japan (didn't know what she wanted lol). So I have no idea if this was an issue from the beginning, or if it was fine for a while and is now a problem.

i also had a big issue with the head drifting (or in my case, falling) backwards, but it was definitely because the resin head i was using with the mdd 2.0 body was way too heavy, especially with the new opening in the back of the neck.

i'm not sure why it'd also be happening with a regular dollfie vinyl head... i do know volks sells little rubber o-rings though that you can place on the neck to secure the head and make sure it doesn't fall back in an unsightly way (mentioned in jadepixel's review of the 2.0 here) !! so perhaps that would fix her problem?

Edited May 26 by cluffy

Ah, I do have some of those that came with my Dream Choice boy. I'll see if they help. Thanks for the suggestion @cluffy