Zhimeng prompts you how to solve the problem of setting the field as linkage type

You set the field as linkage type , However, no linkage group name that is the same as the field name you defined is found in the system !
This is due to stepselect After missing $ Symbol
open /dede/mychannel_field_edit.php file
find  

if($dtype=='stepselect')

Change to

if($dtype=='stepselect$')

  Save and fix the problem .