Hi Tracey,
Hope you are doing well!
Please ensure that you are using the rectangular images to be uploaded as Exhibitor logos also ensure that the images are larger than 300 pixels wide. If the issue persists please follow basic troubleshooting steps to clear cache & cookies from the browser and try again.
Please refer to the helpful article for more information:
Branding Your Exhibitor Portal
Thanks for contacting us.
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Regards,
Neha Kamboj
Quality Analyst I Client Services
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