i change premium stash tab to merchant stash tab, ale i lost all my items from this tab.

i change premium stash tab to merchant stash tab, and i lost all my items from this tab...
Why its no any information about this? how i can know what stash tab i delete and what items i can loose... its so incomprehensible
why this items can't go with tab to this merchant?

Your stash is set to hide Remove Only tabs.

Set it to display them.