I tried to create a simple kanban view.

My Code Below 

Model:

class DoctorDetails(models.Model):
    _name = 'doctor.details'
    _description = 'Doctor Details'
    _rec_name='doctorname'
    doctorname = fields.Char(string="Doctor Name")
    qualification = fields.Char(string="Qualification")
    contactno = fields.Char(string="Contact No")
    doctor_address = fields.Char(string="Doctor Address")

View : 

<record id="doctor_details_kanban" model="ir.ui.view">
    <field name="name">doctor_details.kanban</field>
    <field name="model">doctor.details</field>
    <field name="arch" type="xml">
         <kanban>

             <field name="doctorname"/>
            <field name="qualification"/>
            <field name="contactno"/>
            <field name="doctor_address"/>

              <template>
                     <t t-name="kanban-box">
                     <div class="oe_kanban_card">
                            <strong class="o_kanban_record_title">
                            <field name="doctorname"/>
                            </strong>

                        <div t-if="record.qualification.raw_value">
                                <t t-esc="record.qualification.value"/>
                        </div>
                          <div t-if="record.contactno.raw_value">
                                <t t-esc="record.contactno.value"/>
                        </div>
                            <div t-if="record.doctor_address.raw_value">
                                <t t-esc="record.doctor_address.value"/>
                        </div>
                     </div>
                 </t>
             </template>
         </kanban>
    </field>
</record>

Error : 

Traceback:
TypeError: Cannot read property 'tag' of undefined
    at transformQwebTemplate (http://localhost:8076/web/content/1167-e7e27c3/web.assets_backend.js:2516:53)
    at Class.init (http://localhost:8076/web/content/1167-e7e27c3/web.assets_backend.js:2522:922)
    at Class.prototype.<computed> [as init] (http://localhost:8076/web/content/1058-e416b40/web.assets_common.js:4620:488)
    at new Class (http://localhost:8076/web/content/1058-e416b40/web.assets_common.js:4621:65)
    at Class.getRenderer (http://localhost:8076/web/content/1167-e7e27c3/web.assets_backend.js:340:1833)
    at http://localhost:8076/web/content/1167-e7e27c3/web.assets_backend.js:340:1313
    at async Promise.all (index 0)
    at async Class.getController (http://localhost:8076/web/content/1167-e7e27c3/web.assets_backend.js:1260:569)

kindly do needful