Customizer not working

Hi, I just migrated my website and I’m now having problem with the customizer not loading in or working. All the additional CSS code is still functional and everything else too. Its just the panel and preview window is not loading in, it just says “you are customizing saralinn” and nothing else is showing up. You can’t change preview mode to tablet/phone mode. Customize works on the page where I migrated from. Does anyone know if this is a common problem and how to fix it? I have done all the troubleshooting that is recommended from different forums. Is the solution in changing some files or doing something in the codes. Thanks for the help in advance.

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