how to show admin notice in custom menu page after submitting the form?

It should be add_action not do_action.
And if it still doesn’t work, that means, your form processing code is being triggered after WP fires admin_notices hook.

Related Posts:

  1. What are the standard admin CSS id/class tags?
  2. Admin Ajax is returning 0
  3. Add custom column to Users admin panel
  4. wp_verify_nonce vs check_admin_referer
  5. Add a Separator to the Admin Menu?
  6. How to determine whether we are in add New page/post/CPT or in edit page/post/CPT in wordpress admin?
  7. how to know if admin is in edit page or post [duplicate]
  8. Modal window from within WordPress admin
  9. Where in WP can I check history or log of updates of plugins etc?
  10. Adding a custom admin page
  11. How does admin-ajax.php work?
  12. How to remove entire admin menu?
  13. How do I remove dashboard access from specific user roles?
  14. How can I speed up my WP admin section?
  15. How to pass parameters to admin_notices?
  16. Admin: very slow edit page caused by core meta query
  17. if admin is logged in
  18. Search posts by ID in admin
  19. How to Change the Default Home Page for the WordPress Dashboard?
  20. Setting admin edit panels & metaboxes positions and visibility for ALL users and admins
  21. Find out which moderator approved comment?
  22. The website cannot display the page
  23. How To Remove WordPress Version From The Admin Footer
  24. Sort pages in loop by admin’s page attributes order field?
  25. Edit “thank you for creating with WordPress” in version 3.3.1
  26. Hide other users’ posts in admin panel
  27. Set Default Admin Colour For All Users
  28. Editor Styles and Typekit
  29. WordPress admin stylesheet
  30. This CSS Stuffing Works, But Is This A Good Practice?
  31. Is it possible to create a WordPress tour? V3.3.1
  32. Securing Admin Accounts – Username Discovery
  33. is_admin() returns true when using admin-ajax.php from front end script
  34. How to save dismissable notice state in WP 4.2?
  35. How do I optimize a custom post type admin page with 25,000 posts?
  36. Settings API – adding setting fields dynamically?
  37. Disable Media Uploads to non Admin Users
  38. How do I load a CSS style into WordPress admin area only?
  39. Allowing admin-ajax.php to receive “application/json” instead of “x-www-form-urlencoded”
  40. Can an admin check passwords of registered users?
  41. How can I target WordPress 3.8 new interface MP6 with CSS?
  42. Notification that the admin is online
  43. Does wordpress create activity, update logs?
  44. sort child pages on admin
  45. How-to make the admin area mobile friendly [closed]
  46. How to remove list view from media library?
  47. How to disable the “Your site has updated to WordPress x.y.z” admin email?
  48. Load plugin scripts and styles only on plugin page
  49. Plugin to remove Admin menu items based on user role?
  50. How to obtain the user ID of the current profile being edited in WP-Admin?
  51. 3.3: How do you hide the new dashboard welcome panel?
  52. Add my own button next to “Screen options” and “Help” in the admin
  53. WP List Table custom quick edit box – post meta data missing and columns change on submit
  54. Settings API – easiest way of validating checkboxes?
  55. Are there any action like ‘init_frontend’
  56. Should I use is_admin() inside ‘admin_init’ hook callback
  57. Custom admin email for new user registration
  58. Send Admin Emails to Multiple Email Addresses
  59. How do I set up the defualt page icon for admin menu?
  60. Prevent author from changing their posts if admin has modified
  61. Cannot access admin panel
  62. Make A WordPress Page Accessible To Admins Only, Redirect Other User Roles
  63. Disable all https in WordPress
  64. localhost/wp-admin on my local redirects to production site’s /wp-admin
  65. How to remove administrator role in settings -> general -> New User Default Role?
  66. Is there a more efficient admin search function/plugin?
  67. Can a users profile be put under the dashboard menu
  68. WordPress Admins or Roles per Page
  69. Styling Shortcodes in Visual Editor
  70. initial sort order for a sortable custom column in admin
  71. Showing WP_Error message with admin_notice action hook
  72. WordPress admin screen very slow / timing out when editing or adding a new page/custom post
  73. Uploading files in admin panel?
  74. turn off new user registration emails
  75. Redirect Admin User in Dashboard
  76. Send automatic mail to Admin when user/member changes/adds profile
  77. Create un-removeable user
  78. Get current active wp color scheme
  79. Read only capability for custom post in admin area
  80. WordPress Admin back-end – advanced options page?
  81. Cannot login to WordPress Admin with SSL terminated load balancer
  82. How can ‘admin_email’ be set?
  83. Set Featured Image programmatically (in admin) with JavaScript?
  84. Disable the post save process completely
  85. use add_settings_field properly?
  86. How to change WordPress default strings?
  87. How can we customize the logo and some text on the welcome screen?
  88. front end logo upload like happytables
  89. Can I set a default dashboard layout for all users?
  90. Allow admin login at /admin
  91. Is there a hook to put stylesheet and/or JS inside iframes (thickbox or tinyMCE) in admin area
  92. How to add filter in “Comments” at the admin panel?
  93. Thickbox hacking – removing fields
  94. How to show custom menu items in the WordPress android app?
  95. How to let authors revise other authors drafts, but keep them from publishing?
  96. Modify built-in post type properties
  97. How to fix admin stylesheet muck-up? [closed]
  98. Taxonomy/category hierarchy lost when editing posts [closed]
  99. Custom CSS In Admin Only For Certain Roles
  100. A similar hook as wp_head for the admin area