OMG!! I had the same phone and was having the same problem.... it was really starting to bother me though cuz i thought i had a stalker or something! LMAO! (in reference to the 2nd part of course)
I have the same problem with my Gusto 2 and I'm on my second phone (Verizon could not find a problem and offered to replace the phone). My wife also has a Gusto 2 with the same issues. All the Tips suggested in this thread have been tried and will not correct the problem. After talking to a cell phone development engineer, he is convinced it is the phone. After learning about how "cheap" feature phone circuits are designed without the customary discriminator logic (like the Gusto), calls often will not be received and frequently not placed. In addition, cell boosters/amps can also "confuse" the phone resulting in an error message about not being in a cell area…even with 3 to 4 bars showing. The only fix is to replace the phone with another brand/model. That is what I going to do today. My suggestion to Verizon is to stop selling this phone, now.