You can't have non-stack-able items such as beds in bundles, at least more than one. Default there are two slots with 64 item storage in a bundle, however if you input a bed into the bundle the bundle counts the bed as 64 and doesn't even let you carry two beds.
MC-211116
Beds In Bundles Don't Work
Resolved
Works As Intended
0
Yep, bundles only allow as many items that make one stack of that item