Answer to Ques No 1:
A " communication barrier" or "a barrier to communication" is anything that interferes with the transfer of intended information from a sender to a receiver.
Answer to Ques No 2:
We can maintain personal contact through Three Common Barriers. They are Physical, Psychological, Cultural.
Physiological barriers :
Deafness or hearing loss
•Blindness or impaired vision
Cultural barriers :
•Each cultural group has beliefs and practices regarding health and illness.
Psychological barriers :
For example, if someone is stressed they may be preoccupied by personal concerns and not as receptive to the message as if they were not stressed.