Small Business - can't manage Small business in the tab

I have a Sims with a Small business - the Small Business tab stopped working, and I can only manage it through the kiosk item - so I can only open, close, sell and manage the pricing, but no option to manage employees. 

When clicking on the New Business tab, it shows the option to register a new small business - but nothing happens when clicking the button, as I already have it installed. 

The issue started yesterday when I took my sim to the Llama Finchwick Fair. When returning to the lot, the Small Business tab was not working anymore. It fixed itself for a second, but I still wasn't able to hire and manage employees, I would select sims to hire and no action would take place.