Phone [Q] Help: How to remove cwm on tecno l3 mtk device

Developers in the house, I need your help on how to remove cwm on my tecno l3 ie returning it to stock or how I bought it. I have a stock rom dump from a friend. I have rooted the phone and flashed it with cwm but before doing it I did a backup which was having a .backup extension and hard reset the phone. After the installation of the cwm, I couldn't use the backup again. The only thing that I need from the backup file are my contacts and messages. I have tried all my best to extract from this backup but no success. PS: I hard reset my phone and then rooted it because it was locked due to wrong pattern by a friend, so the backup I made before resetting still contains the settings. Anyway to go about this? I will surely appreciate all suggestions and solutions. Thanks.
your new guy,
kayode