When the start date and end date of an SP activity are the same, changing the end date of this activity to no end date will result in an error: START_DATE_AFTER_END_DATE，Start date cannot be after end date.

[CoderWeiAden]

When the start date and end date of an SP activity are the same, changing the end date of this activity to no end date will result in an error:
START_DATE_AFTER_END_DATE，Start date cannot be after end date.

the interface is :
https://advertising.amazon.com/API/docs/en-us/sponsored-products/3-0/openapi/prod#tag/Campaigns/operation/UpdateSponsoredProductsCampaigns

my param is:
{
"campaigns": [
{
"campaignId": "289634794537571",
"portfolioId": "240367241152955",
"endDate": null,
"name": "ZXSVT9-sp-Yamila-test0906",
"targetingType": "AUTO",
"state": "PAUSED",
"dynamicBidding": {
"placementBidding": [
{
"percentage": 0,
"placement": "PLACEMENT_TOP"
},
{
"percentage": 0,
"placement": "PLACEMENT_PRODUCT_PAGE"
},
{
"percentage": 0,
"placement": "PLACEMENT_REST_OF_SEARCH"
}
],
"strategy": "LEGACY_FOR_SALES"
},
"startDate": "2026-10-01",
"budget": {
"budgetType": "DAILY",
"budget": 1
},
"tags": {
"property1": "{"businessId":"1832004097431105537"}"
}
}
]
}

the result is :

When the start date and end date do not match, this situation will not occur

[DrRockett]

Hi, I'm curious if this was your intended actual use case, or were you just testing? i.e., did you actually want to create a campaign with the exact same start and end date?

[CoderWeiAden]

Hi, I'm curious if this was your intended actual use case, or were you just testing? i.e., did you actually want to create a campaign with the exact same start and end date?

yes，i wanna to create a campaign for the begin date and end date is same。