Hi my boot cover is stuck in my 2019 E220 estate. The curtain is extended by about a foot and a half but won’t reach the guide grooves in the side wall of the boot. I released it last night to transport a tall item. Today it won’t retract or release. There is nothing in the manual that I can find on this. No error message on the dashboard. I need the curtain to work to cover my boot items. Do I have to buy a whole new curtain ? I have released it from its fittings either side in an effort to ‘reset’ to no avail.