Errors in income tax 143(1) intimations

Hi

Today I checked around 6 intimations u/s 143(1) and found that 2 of them are wrongly calculated. In one of the intimations speculative income is added same as non speculative business income whereas speculative income was only Rs. 300 and raised demand.
In another case speculative loss has been added in non speculative income and increasing the real income.

Please guide me how should I proceed. Which is the better way rectification u/s 154 or a simple email stating facts to CPC, Bengaluru.

Regards.