I imported my Tumblr blog to Wp but all my blog are showing the preceding date as the date of publishing. I even changed the timezone of my wp account to my location before importing but the problem persists.
Option 1 (no code): you can manually edit each post and change the published date. Look in the "Publish" box where you publish or update posts, and there will be a "published on" date with an "edit" link.
Option 2 (requires database access): you can run a MySQL query to adjust all posts' dates.
UPDATE wp_posts SET post_date = DATE_ADD(post_date,INTERVAL 1 DAY) WHERE post_type = 'post'; UPDATE wp_posts SET post_date_gmt = DATE_ADD(post_date_gmt,INTERVAL 1 DAY) WHERE post_type = 'post';
There are two lines because WP stores both a local timezone timestamp and a GMT timestamp.
This assumes your database uses the default
wp_ prefix - you should first back up your database, then check which prefix you use, and if it's a different prefix then just update
wp_posts in both lines to whatever yours is called.