Kingkrish, what formation do you use right now?
When I was lvl. 12 I used the 3-4-3 formation, and I won the season thanks to it. If you wanna know the tactics of this formation there is a video made by me: https://www.youtube.com/watch?v=C5fDxWyKELc (I explained everything there.)
You can use the 3-5-2 V style. (dc-dc-dc or dl-dc-dr / dmc / mc - mc/ aml - amr / st- st) It's a good formation too.
Also I suggest to put the 4-1-4-1 (dl-dc-dc-dr / dmc / ml - mc - mc - mr / st) with advanced ML&MR.