So, as of a few months ago, Authorize.net no longer functions with iframe. We have had conversations that say that Wix can change some parameters in order for the Authorize Simple Checkout html code to function within Wix. Is this true?
Why use the html code through the html iframe, you are much better and more secure using Authorize own API through Wix Fetch.
https://support.wix.com/en/article/corvid-accessing-third-party-services-with-the-fetch-api
https://www.wix.com/corvid/reference/wix-fetch.html
https://stackoverflow.com/questions/56114250/how-do-i-integrate-authorize-net-into-my-wix-page
Also, have a look at json stringify and json parse.
https://www.w3schools.com/js/js_json_stringify.asp
https://www.w3schools.com/js/js_json_parse.asp
Have a look at Authorize own info about their api.
https://developer.authorize.net/api/reference/index.html
https://developer.authorize.net/api/
You can add Authorize as a payment through Wix.
https://support.wix.com/en/article/setting-up-authorizenet-as-a-payment-gateway-for-wix-restaurants