cannot take screenshot

i wanna ask for take screeen shot on web, after do step take screeen show this error.

12-06-2018 11:52:03 AM Test Cases/Adam/Web/Branch Portal Cloud - Log by ID

Elapsed time: 46.089s

Test Cases/Adam/Web/Branch Portal Cloud - Log by ID FAILED.

Reason:

com.kms.katalon.core.exception.StepFailedException: Unable to take screenshot (Root cause: com.kms.katalon.core.exception.StepFailedException: No driver found)

at com.kms.katalon.core.keyword.internal.KeywordMain.stepFailed(KeywordMain.groovy:36)

at com.kms.katalon.core.mobile.keyword.internal.MobileKeywordMain.stepFailed(MobileKeywordMain.groovy:40)

at com.kms.katalon.core.mobile.keyword.internal.MobileKeywordMain.runKeyword(MobileKeywordMain.groovy:23)

at com.kms.katalon.core.mobile.keyword.builtin.TakeScreenshotKeyword.takeScreenshot(TakeScreenshotKeyword.groovy:83)

at com.kms.katalon.core.mobile.keyword.builtin.TakeScreenshotKeyword.execute(TakeScreenshotKeyword.groovy:73)

at com.kms.katalon.core.keyword.internal.KeywordExecutor.executeKeywordForPlatform(KeywordExecutor.groovy:53)

at com.kms.katalon.core.mobile.keyword.MobileBuiltInKeywords.takeScreenshot(MobileBuiltInKeywords.groovy:166)

at com.kms.katalon.core.mobile.keyword.MobileBuiltInKeywords$takeScreenshot.call(Unknown Source)

at Branch Portal Cloud - Log by ID.run(Branch Portal Cloud - Log by ID:27)

at com.kms.katalon.core.main.ScriptEngine.run(ScriptEngine.java:194)

at com.kms.katalon.core.main.ScriptEngine.runScriptAsRawText(ScriptEngine.java:119)

at com.kms.katalon.core.main.TestCaseExecutor.runScript(TestCaseExecutor.java:321)

at com.kms.katalon.core.main.TestCaseExecutor.doExecute(TestCaseExecutor.java:312)

at com.kms.katalon.core.main.TestCaseExecutor.processExecutionPhase(TestCaseExecutor.java:291)

at com.kms.katalon.core.main.TestCaseExecutor.accessMainPhase(TestCaseExecutor.java:283)

at com.kms.katalon.core.main.TestCaseExecutor.execute(TestCaseExecutor.java:222)

at com.kms.katalon.core.main.TestCaseMain.runTestCase(TestCaseMain.java:106)

at com.kms.katalon.core.main.TestCaseMain.runTestCase(TestCaseMain.java:97)

at com.kms.katalon.core.main.TestCaseMain$runTestCase$0.call(Unknown Source)

at TempTestCase1544071919646.run(TempTestCase1544071919646.groovy:22)

pls help for this issue.
thx

Could you please share your script?