Espruino keeps disconnecting

Hello, I have a problem with Espruino Pico on Mac.
When I plug it in, red light flashes and then nothing flashes.
When I connect espruino tty.usbmodem1 it connects and after a while it disconnects.
When I want to connect it again, connection options state tty.usbmodem2 and again disconnects.
I tried to reflash the firmware (with success) but still the same.

Sometimes it writes this log:

Connected
>es from flash...
>Console Moved from Serial1
>
=undefined
>echo(0);
<<<<<{"VERSION":"1v81","BUILD_DATE":"Oct­  8 2015","BUILD_TIME":"16:03:41","GIT_COMMI­T":"8e1efcf898350a290242d732631be15c36f5­3381","BOARD":"PICO_R1_3","CHIP":"STM32F­401CDU6","CHIP_FAMILY":"STM32F4","FLASH"­:393216,"RAM":98304,"SERIAL":"63004700-1­3513430-36363435","CONSOLE":"USB","EXPOR­TS":{"jsvLock":182749,"jsvLockAgainSafe"­:182737,"jsvUnLock":182713,"jsvSkipName"­:120321,"jsvMathsOp":209729,"jsvMathsOpS­kipNames":277173,"jsvNewFromFloat":20996­1,"jsvNewFromInteger":210029,"jsvNewFrom­String":124953,"jsvNewFromBool":209985,"­jsvGetFloat":203841,"jsvGetInteger":2046­57,"jsvGetBool":204105,"jspeiFindInScope­s":210601,"jspReplaceWith":135865,"jspeF­unctionCall":115713,"jspGetNamedVariable­":140209,"jspGetNamedField":229317,"jspG­etVarNamedField":228953,"jsvNewW
Disconnected
> 

Can you help me