Im on my post covid phase right now.i tested negative few days back.some people are telling me i have the high chances of getting reinfected within 3 months.is it true?

Have no clue who "some people" are, but will state that lots of fake news is present. Some rare cases of reinfection with Delta variant have been seen in those who have had native COVID-19, even if vaccinated. To be safest, get the jab when you are 90 days past the original infection.

The re infection rate is quite low, but continue to use a mask and social distancing. Use good hand washing. A COVID 19 vaccination is indicated in three months. Family members should be vaccinated.