Facebook ad account couldn't be added due to max number of allowed ad accounts

[jkids]

Hi folks, seeking advice here.

I have added and create Facebook pixel to the store through the "preferences" tab, then added Facebook as a sales channel. When I try to connect the ad account I especially created to run campaigns for this business, I encountered the error message in screenshot below. I read up on how to Troubleshoot Ad Account Creation Issues on FB Business Help Centre, and none of the conditions apply to me. I would like to contact Facebook and fix this so I can run ads, but cannot find a way to reach them.

Has anyone encountered a similar issue and managed to solve this? I'd be grateful for the pointers!