Can´t find datepicker

I have a problem with a
unit test. Use Katalon and find all the fields LESS the datepicker …
in them it falls and it gives an error when I select a from a datepicker

09-08-2018 12:00:00 PM - [INFO] - Finding web element with id:
‘Object Repository/Page_Escritorio Acepta/a_1’ located by ‘By.xpath:
id(“ui-datepicker-div”)/table[@class=“ui-datepicker-calendar”]/tbody[1]/tr[1]/td[@class=""]/a[@class=“ui-state-default
ui-state-hover”][count(. | //a[@href = ‘#’ and (text() = ‘1’ or . =
‘1’)]) = count(//a[@href = ‘#’ and (text() = ‘1’ or . = ‘1’)])]’ in ‘30’
second(s)

Luego da este error

09-08-2018 12:00:38 PM - [FAILED] - Unable to click on object ‘Object
Repository/Page_Escritorio Acepta/a_1’ (Root cause:
com.kms.katalon.core.webui.exception.WebElementNotFoundException: Web
element with id: ‘Object Repository/Page_Escritorio Acepta/a_1’ located
by ‘By.xpath:
id(“ui-datepicker-div”)/table[@class=“ui-datepicker-calendar”]/tbody[1]/tr[1]/td[@class=""]/a[@class=“ui-state-default
ui-state-hover”][count(. | //a[@href = ‘#’ and (text() = ‘1’ or . =
‘1’)]) = count(//a[@href = ‘#’ and (text() = ‘1’ or . = ‘1’)])]’ not
found)

In other words, I can not click on the date (selected day)