ERROR TypeError: IamportCapacitor.startIamportActivity is not a function

[dev-fath]

아임포트 테스트 중 다음과 같은 에러가 발생하여 문의드립니다.

ERROR TypeError: IamportCapacitor.startIamportActivity is not a function
    at IMP.certification (plugin.js:93)
    at PurchasePage.handleClickCertification (purchase.page.ts:46)
    at PurchasePage_Template_ion_button_click_13_listener (purchase.page.html:14)
    at executeListenerWithErrorHandling (core.js:15225)
    at wrapListenerIn_markDirtyAndPreventDefault (core.js:15260)
    at HTMLElement.<anonymous> (platform-browser.js:582)
    at ZoneDelegate.invokeTask (zone-evergreen.js:399)
    at Object.onInvokeTask (core.js:27492)
    at ZoneDelegate.invokeTask (zone-evergreen.js:398)
    at Zone.runTask (zone-evergreen.js:167)
defaultErrorLogger @ core.js:4442
handleError @ core.js:4490
handleError @ core.js:8775
executeListenerWithErrorHandling @ core.js:15228
wrapListenerIn_markDirtyAndPreventDefault @ core.js:15260
(anonymous) @ platform-browser.js:582
invokeTask @ zone-evergreen.js:399
onInvokeTask @ core.js:27492
invokeTask @ zone-evergreen.js:398
runTask @ zone-evergreen.js:167
invokeTask @ zone-evergreen.js:480
invokeTask @ zone-evergreen.js:1621
globalZoneAwareCallback @ zone-evergreen.js:1647