Can you get infected second time with covid even though youre vaccinated? is it a common thing or rare?

There are a high number of reported "break through cases" in vaccinated persons. Each subsequent infection will be milder because you now have immunity to the virus. It may feel like a cold. It is still important to be tested if you have any covid symptoms (cough, headache, fever, runny nose, sore throat) in order to prevent spreading the illness to others.

You can get infected after a natural infection with Covid or after vaccination. However, the vaccination protects you against serious illness and hospitalizations. The exact frequency of "breakthrough" infections is not clear.