What should I do if my tourist visa application for Thailand requests an invitation but we don't have one?

Hi everyone I'm hoping you can help, myself and my partner are in the process of applying for the tourist visa, we had read into it prior to applying and gathered all the necessary documentation, however, the visa site is now asking me to add a passport picture and identity the person inviting us to stay there e.g. Thai ID card, Passport, but we do not have anyone inviting us over. We are going as tourists and thought we'd only need proof of flights, accommodation and a bank statement in order to process with our visas. Has anyone had this problem or know what we need to do? Thanks in advance :)