$('#iTTDateOpen').data('datetimepicker').setLocalDate(new Date(2019, 6, 2, 10, 55));

<div class="form-group">
<label class="col-md-3 control-label">TT Date Open</label>
<div class="col-md-7">
<input type="text" id="iTTDateOpen" class="form-control txt filter-time" placeholder="Trouble Ticket Date Open" onkeydown="return false" required>
</div>
</div>