Hello i cant add any new supplier or customer in the expenses majol and it doesnt even work . so i tried adding new ones in new journal entry and it doesnt work

Happy to help, Parvaneh.

I have troubleshooting steps to help fix the unable to add supplier or customer problems in QuickBooks. Happy to share with you the complete steps. 

Sometimes, too much cache build-up in your regular browser can cause unexpected behavior in the product. It sounds like your server was interrupted or corrupted. With this, I'd recommend logging your account through incognito. This way, we can check if it's a browser-related issue. 

Refer to the keyboard shortcuts below:

• Ctrl + Shift + N (Google Chrome)
• Ctrl + Shift + P (Firefox)
•  Control + Option + P (Safari)
•  Ctrl + Shift + P (Microsoft Edge)

Once in, add the new supplier or customer to verify if they're functioning well. If it's solved, return to your regular browser and press the CTRL+ Shift and Delete keys on the keyboard to clear the cache.

To learn how to add, edit, delete, or merge customers or suppliers in QuickBooks, visit these articles below:

• Add and manage customers in QuickBooks Online
• Add a supplier in QuickBooks Online

I've also included these resources that'll guide you in managing your sales transactions in QuickBooks:

• Invoices and Payments commonly asked questions.
• Expenses and suppliers FAQs

If you have more questions about handling your tenant's transaction, I'm always here to help. Keep safe!