Opinions needed: GLA making strange noises when when naturally decelerating

[LPJ]

Hi All

I got a 2018 GLA220d, under 50,000 miles and last night it was making a strange sound and rattling. What could it be? It only happens when naturally decelerating from 20-10mph, with extreme rattle and weird noise.

Uploaded a video on YouTube for you to see/hear the problem.

Any thoughts would be appreciated!

Thanks!