How to fix url not founds after changing link structure

Recently changed permalink structure in WordPress from


Now all of my old posts are URL not found . Guessing that is 404.

Instead of helping SEO I think I have killed it. is there any way to have link structure work
both with both old posts and with new posts using the post name as URL ?

Hope this makes sense

No body had this issue themselves?

No, but a search yielded this:

Fixed ny updating the htaccess with the following in case anyone else runs into this trouble. Thank you Sdayman

RewriteRule ^([0-9]+)/([0-9]+)/([0-9]+)/(.*)$ /$4 [R=301,NC,L]