Angular 2 dragulaModel throws Cannot read property 'splice' of undefined exception

Question

I am using ng2-dragula and with data binding in 2 tables. When a td is drag and drop to another table, it throws the Uncaught TypeError: Cannot read property 'splice' of undefined. and is not able to drop the element. Need help on how to resolve this problem.

Below is the html part

    <table class="table">
        <thead class="text-primary">
            <tr>
                <th>Task ID</th>
                <th>Ref #</th>
                <th>Customer Name</th>
                <th>Doc Type</th>
                <th>Date</th>
            </tr>
        </thead>
        <tbody [dragula]='"team-bag"' [dragulaModel]="tasks">
            <tr *ngFor="let t of tasks">
                <td>{{t.id}}</td>
                <td>{{t.refNbr}}</td>
                <td>{{t.custName}}</td>
                <td>{{t.docType}}</td>
                <td>{{t.receiveDate}}</td>
            </tr>
        </tbody>
    </table>
    
        <table class="table">
        <thead class="text-primary">
            <tr>
                <th>Task ID</th>
                <th>Ref #</th>
                <th>Customer Name</th>
                <th>Doc Type</th>
                <th>Date</th>
            </tr>
        </thead>
        <tbody [dragula]='"team-bag"' [dragulaModel]="agentATasks">
            <tr *ngFor="let t of agentATasks">
                <td>{{t.id}}</td>
                <td>{{t.refNbr}}</td>
                <td>{{t.custName}}</td>
                <td>{{t.docType}}</td>
                <td>{{t.receiveDate}}</td>
            </tr>
        </tbody>
    </table>

tasks and agentATasks are both defined and populated in the component.ts.

Below is the error in Chrome console. Subscriber.ts:241 Uncaught TypeError: Cannot read property 'splice' of undefined at Object.eval (http://localhost:3002/node_modules/ng2-dragula/components/dragula.provider.js:94:28) at emitter (http://localhost:3002/node_modules/contra/emitter.js:47:72) at Array.forEach (native) at Object.eval (http://localhost:3002/node_modules/contra/emitter.js:46:10) at Object.thing.emit (http://localhost:3002/node_modules/contra/emitter.js:38:48) at drop (http://localhost:3002/node_modules/dragula/dragula.js:261:13) at HTMLHtmlElement.release (http://localhost:3002/node_modules/dragula/dragula.js:245:7) at ZoneDelegate.invokeTask (http://localhost:3002/node_modules/zone.js/dist/zone.js:265:35) at Object.onInvokeTask (http://localhost:3002/node_modules/@angular/core/bundles/core.umd.js:5967:41) at ZoneDelegate.invokeTask (http://localhost:3002/node_modules/zone.js/dist/zone.js:264:40)