Hi,

Please refer to the following links:

1. https://www.cybrosys.com/blog/how-to-customize-header-footer-for-all-reports-in-odoo-16-erp

2. https://www.cybrosys.com/blog/how-to-customize-headerfooter-for-all-reports-in-odoo-18

Hope it helps.

Either use any other Document Layout than DIN5008 (Settings -> General Settings --> Companies --> Document Layout -> Configure Document Layout), or extend l10n_din5008.external_layout_din5008 so it doesn't loop over the first two but only the first bank, i.e.

<t t-foreach="company.partner_id.bank_ids[:1]" t-as="bank">

instead of

<t t-foreach="company.partner_id.bank_ids[:2]" t-as="bank">

(https://github.com/odoo/odoo/blob/18.0/addons/l10n_din5008/report/din5008_report.xml#L140)

Note: You could change the template in Settings -> Technical --> User Interface -> Views - but, any upgrade of the module l10n_din5008 will reset it to its original state again (hence, the template should be extended in a custom module rather than directly in Odoo).