I'd be happy to share some troubleshooting steps for you to resume uploading logos in QuickBooks Online. Let's begin by opening your account in a private browser. When there's too much data in the cache, it can potentially cause performance issues within the program. You may try these keyboard shortcuts:
If you're still getting the same behavior, I would recommend contacting our QuickBooks Care Team. They have the tools to escalate this behavior to our engineers for further investigation. Here's how to contact us:
Click the (?) Help menu at the top right section of your QBO Dashboard.
Tap the Contact us button.
Keep me updated on the result or if you need further help. I'm here to lend you a hand whenever you need one. Wishing you all the best!