hi, im on the process of integration of paypal with odoo, but it seems that im stuck! i already installed modules like (e-commerce, accounting, Paypal, EDI and the likes) to work paypal integration, when i am in the Accounting>>invoice and i selected transaction there is a blue strip where there should be a paypal button there but it only contains a text saying ex." 100.00 Php   Play Safe Online" , my problem is there is no button showing that links this payment to paypal, anyone encountered this kind of problem?  i already tried this to odoov9 and v8 and i think its not a proble on the version.