Snehanand Sinha

I have a Maltipoo male puppy 6.5 months old. He is increasingly getting more nervous and resource guards his food, bed, and at times anything and everything. When anxious he tends to be stiff, have a blank stare, lunges even when unprovoked, and at times gets around to bite too. Fortunately, he backs off when you are firm and stay in the same place. This behaviour is more pronounced between 8pm and 7am. During the day he is far less anxious. Please recommend steps to take