First, I downloaded  and installed the report xlsx module by OCA, then go to: Settings >> General Settings >> Technical >> Reporting >> Reports >> Sales Details

to change from pdf to xlsx, save and try printing and it's generating an error message below:
AttributeError: 'report.point_of_sale.report_saledetails' object has no attribute 'create_xlsx_report' The above server error caused the following client error: RPC_ERROR: Odoo Server Error RPC_ERROR at makeErrorFromResponse (http://localhost:1800/web/assets/6e560ce/web.assets_web.min.js:3116:163) at decoder.onload (http://localhost:1800/web/assets/6e560ce/web.assets_web.min.js:3102:7)

Please I don't mind paying a token for this help, thanks!