Not able to use with-timezone , errors if the timezone is active

[gaxolio]

Hi, until now i have used the component without timezone, without any problem.
Now I have added the property to the component with-timezone="true".
Everything seems to work, date, time and timezone are displayed correctly when I click on icon that set the now date/time/timezone.
The problem appears when I try to change the values of the timezone, hours or minutes.
When I click on icon that increment/decrement timezone hours/minutes console errors appear in the console like this:
property-effects.js:245 Uncaught RangeError: Maximum call stack size exceeded at Object.runObserverEffect [as fn] (property-effects.js:245) at runEffects (property-effects.js:146) at HTMLElement._propertiesChanged (property-effects.js:2160) at HTMLElement._flushProperties (properties-changed.js:424) at HTMLElement.__enableOrFlushClients (property-effects.js:2040) at HTMLElement._flushClients (property-effects.js:2012) at HTMLElement._propertiesChanged (property-effects.js:2155) at HTMLElement._flushProperties (properties-changed.js:424) at HTMLElement._invalidateProperties (property-effects.js:1969) at HTMLElement.setProperties (property-effects.js:2088)
At this point the date and time are shown completely wrong.

My environment.
[email protected]
[email protected]
nodejs 14.15.1
express 4.17.1

<datetime-picker class="custom" value="{{pkvalue}}" date="{{pkdate}}" datetime="{{pkdatetime}}" time="{{pktime}}" with-timezone="true" hour12-format="false" </datetime-picker>
these compnents are imported:
import {PolymerElement, html} from '../../node_modules/@polymer/polymer/polymer-element.js';
import {SmoAppLocalizeBehaviorImpl} from '../smo-app-localize-behavior/smo-app-localize-behavior.js';
import {afterNextRender} from '../../node_modules/@polymer/polymer/lib/utils/render-status.js';
import '../../node_modules/@polymer/paper-card/paper-card.js';
import '../../node_modules/@polymer/paper-button/paper-button.js';
import '../../node_modules/@polymer/paper-dialog/paper-dialog.js';
import '../../node_modules/@polymer/paper-listbox/paper-listbox.js';
import '../../components/smo-func/smo-func.js'; my functions
import '../../node_modules/@fooloomanzoo/datetime-picker/datetime-picker.js';
import '../../components/smo-action-management/simple-confirm-dialog.js'; my component

Sergio