well if that phone is not defective, and this has happened with a different phone, then there is still some equipment that is connected to your line that is defective... it is pre-tripping, which 80% of the time or more is defective equipment connected to your phone line inside your home...
these conditions usually occur after a power surge (namely a lightning storm) on your phone line, damaging the internal electrical components of the phone creating a short when ringing current is placed on your line...
what happens when you call your line with this phone disconnected from your line.. do you get more than 2 rings - if yes, then this phone is defective... if no, then there is something else that is the problem.. what else is connected to your phone line? if you have an alarm system connected to your phone line that is likely going to be the problem...
there are some occasions where this may be an outside trouble.. if the phone company told you that the phone is defective when you called them, but did not come out and check your line, you may want to go to the NID on the outside of your house and connect a working corded phone there, and test if the incoming calls work - if they do, the problem is inside, if not, then it is an outside problem and the phone company needs to be called to make the repairs outside...
to prevent this from occurring again (if the trouble is inside) you should place a telephone line surge protector at the main DEMARC