Rush not exporting full length video

Hi everyone,

I have a 16 min timeline on mobile rush but when I export it, the final video comes out aroundonly 13 mins.

I have tried removing/reshuffling clips to see if there any any particular glitches but no luck.

It did successfully render it in two bits (duplicationg and splitting mu timeline in two sections @ 0-13 mins and then 13-16 mins). What would be the best way to get help around this? 

Thank you in advace.