Bank of America Europe transaction dispute.

There is no form for customers of Bank of America, instead its all done in app.

Quote from Bank of America Europe:

"Before initiating a claim

Consider calling the merchant first, as they may resolve your claim faster (we may also require information from the merchant to process a claim, so contacting them directly may save you time).

Only posted transactions can be disputed (pending charges are temporary and may change). If you have any immediate concerns about a pending charge, contact the merchant directly.

The merchant's contact information is typically found on your receipt or billing statement..."

Direct link: https://www.bankofamerica.com/help/how-to-dispute-a-charge/