Errors occurred after WordPress 5.4 upgrade

react-dom.min.js?ver=16.9.0:103 TypeError: m.find is not a function
at block-editor.min.js?ver=704b9a6d689b18b6982a8b2ae902e7ec:50
at Array.reduce (<anonymous>)
at block-editor.min.js?ver=704b9a6d689b18b6982a8b2ae902e7ec:50
at Object.useMemo (react-dom.min.js?ver=16.9.0:205)
at useMemo (react.min.js?ver=16.9.0:32)
at Me (block-editor.min.js?ver=704b9a6d689b18b6982a8b2ae902e7ec:50)
at block-library.min.js?ver=f710d3cc99e7a55a0d6a5418f3cfe33c:9
at je (react-dom.min.js?ver=16.9.0:78)
at ph (react-dom.min.js?ver=16.9.0:215)
at lh (react-dom.min.js?ver=16.9.0:126)

throws this error in console. Doesn’t support my current theme Zox news. After upgrading to 5.4 wordpress, switching back to initial theme solves the problem. Please help me what should I change in my theme to make this work.