Spring wooden frame for the Ikea Malm bed 140cm is too wide

I have a Malm bed in 140cm width. I just bought a new slatted frame (with a frame, before I had one without a frame ...). Problem: The piece slips through because there is > 2cm of clearance and the metal rails are way too narrow.

My roommate apparently had the same problem, I have to ask him tomorrow how he solved it.

Any suggestions? Taking Ikea to task for improvements is out of the question, the bed is already older than 2 years ...

I would simply have a few wooden slats cut to the right length at the hardware store and place them underneath. So just create a new frame.

Best regards Expedit

I have exactly the same problem. So it's not really that bad, because my mattress is simply about 2 cm lower on one side than on the other. But it does look dumb. I am also thankful for advice :)