can’t add body text

Hello
I have updated WordPress to version 5.6.2, but after the update, the classic editor does not allow me to add the body text I can add the only title and the body editor disabled like read-only,
I have installed jQuery Migrate Helper and he shows me those errors :

https://www.domain.org/wp-admin/js/common.min.js: jQuery.fn.delegate() is deprecated
https://www.domain.org/wp-admin/js/media-upload.min.js: jQuery.fn.resize() event shorthand is deprecated
https://www.domain.org/wp-admin/js/iris.min.js: jQuery.isArray is deprecated; use Array.isArray
https://www.domain.org/wp-admin/js/iris.min.js: jQuery.expr[':'] is deprecated; use jQuery.expr.pseudos
https://www.domain.org/wp-admin/js/iris.min.js: jQuery.isFunction() is deprecated
https://www.domain.org/wp-admin/js/color-picker.min.js: jQuery.isArray is deprecated; use Array.isArray
https://www.domain.org/wp-admin/js/color-picker.min.js: jQuery.expr[':'] is deprecated; use jQuery.expr.pseudos
https://www.domain.org/wp-admin/js/color-picker.min.js: jQuery.isFunction() is deprecated
https://www.domain.org/wp-content/plugins/ninja-forms/assets/js/lib/combobox.min.js: jQuery.isArray is deprecated; use Array.isArray
https://www.domain.org/wp-content/plugins/ninja-forms/assets/js/lib/combobox.min.js: jQuery.expr[':'] is deprecated; use jQuery.expr.pseudos
https://www.domain.org/wp-content/plugins/ninja-forms/assets/js/lib/combobox.min.js: jQuery.isFunction() is deprecated
https://www.domain.org/wp-content/plugins/relevant/bws_menu/js/general_script.js: jQuery.fn.bind() is deprecated
https://www.domain.org/wp-content/plugins/ninja-forms/assets/js/lib/jBox.min.js: jQuery.type is deprecated
https://www.domain.org/wp-admin/js/common.min.js: jQuery.fn.click() event shorthand is deprecated
https://www.domain.org/wp-admin/js/common.min.js: jQuery.fn.bind() is deprecated
https://www.domain.org/wp-admin/js/common.min.js: jQuery.fn.mousedown() event shorthand is deprecated
https://www.domain.org/wp-admin/js/common.min.js: jQuery.fn.focus() event shorthand is deprecated
https://www.domain.org/wp-admin/js/postbox.min.js: jQuery.fn.click() event shorthand is deprecated
https://www.domain.org/wp-admin/js/postbox.min.js: jQuery.fn.bind() is deprecated
https://www.domain.org/wp-admin/js/post.min.js: jQuery.fn.focus() event shorthand is deprecated
https://www.domain.org/wp-admin/js/post.min.js: jQuery.fn.blur() event shorthand is deprecated
https://www.domain.org/wp-admin/js/tags-box.min.js: jQuery.trim is deprecated; use String.prototype.trim
https://www.domain.org/wp-admin/js/tags-box.min.js: jQuery.fn.click() event shorthand is deprecated
https://www.domain.org/wp-admin/js/tags-box.min.js: jQuery.fn.keypress() event shorthand is deprecated
https://www.domain.org/wp-admin/js/tags-suggest.min.js: jQuery.isFunction() is deprecated
https://www.domain.org/wp-admin/js/tags-box.min.js: jQuery.fn.submit() event shorthand is deprecated
https://www.domain.org/wp-admin/js/post.min.js: jQuery.fn.click() event shorthand is deprecated
https://www.domain.org/wp-admin/js/post.min.js: jQuery.fn.keypress() event shorthand is deprecated
https://www.domain.org/wp-admin/js/post.min.js: jQuery.fn.change() event shorthand is deprecated
https://www.domain.org/wp-admin/js/svg-painter.js: jQuery.fn.hover() is deprecated
https://www.domain.org/wp-content/plugins/wp-smushit/app/assets/js/smush-admin.min.js: jQuery.fn.focus() event shorthand is deprecated
https://www.domain.org/wp-content/plugins/wp-smushit/app/assets/js/smush-admin.min.js: jQuery.fn.click() event shorthand is deprecated
https://www.domain.org/wp-content/plugins/autoptimize/classes/static/toolbar.js: jQuery.type is deprecated

please could you tell me how to fix this issue?
Best Regards

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