Letv — getting calls from numbers frequently which have been blocked

Address:

110095

Sir,
I`m getting calls from the numbers which have been blocked by letv phone frequently. I`ve been receiving spam calls especially from those numbers which have been blocked. Even the truecaller in this phone is not working. If this continues i will have to change my sim which i`m not willing to do so. So i request you to help me out with this problem.
Phone: letv leeco le 2