ajax-admin.php return 400 sometimes

Hi experts,
Issue: go to single product page, click the reservation date and return ajax call error 400, this is happend once a which, not all the time
Processing: go to like this product page: , then click reservation date, it will show the total_cost price in the same page via ajax call

Env: wp 5.3/ php 7/

Resolution:
I had looking about add_to_cart boutton which call ajax for woocommerce to pass the cart page, some mentions it might be cache issue, but not sure if this is had to fix cache issue since from document list to disable cache ( my version wp is new), and this issue was not occur until recently add some feature for product, but not related to any ajax function, more with product descriptions

Hope if anyone have this kind of problem please share the solution, tks

• This topic was modified 5 years, 1 month ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Developing with WordPress topic

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