I would check a few things:
Are you one hundred percent sure you are running the right program? I can't
tell you how many times I have had to make a kid show me the program on the
laptop and the program they are running on the EV3 and it turned out they
were running the wrong program. Give the program a unique name (other than
"program"!) and verify.
Check to make sure all of the cables are plugged into the EV3 securely.
Reboot the EV3
Are you using the gyro? There are certainly some issues with the gyro that
are well documented.
Are you sure the program blocks operating the motors are commanding the
right ports?

Hopefully one of these will help.


On Sun, Nov 3, 2019 at 11:33 PM masahide okada <
[log in to unmask]> wrote:

> Hi!
> Thanks for the advice! Is it possible for as single program in a project
> (on the computer) to have a bug? We tried deleting the one program on the
> computer that the robot was not following properly, and rewrote it in
> exactly the same way. This seems to have solved the problem though we
> haven’t tested it enough to know for sure. Unfortunately, even if it did
> work, we don’t know what caused it, so we are unsure how to prevent it from
> happening again. Any thoughts?
> Thanks,
> Rosanna
>
> Sent from my iPhone
>
> On Nov 3, 2019, at 5:10 PM, srinivasalu s <[log in to unmask]> wrote:
>
> 
> Try deleting all programs and download it once again.
> On Sun, Nov 3, 2019, 4:00 PM masahide okada <
> [log in to unmask]> wrote:
>
>> Hi all,
>>
>> Our tournament is November 10 and our EV3 brick has just started going
>> crazy on us. It followed programs beautifully yesterday afternoon, we
>> turned it off, plugged it in to charge it, and then turned it on again an
>> hour or two later to show someone the new programs. This is when the robot
>> started acting strangely, for example, going backwards when the program
>> (that it followed before) says to go forward.
>>
>> The team has tried charging the battery overnight, checking for software
>> updates (none), updated the firmware, unplugging and replugging in all the
>> cables, restarting the app on the computer (a Dell). We even tried a new
>> brick. Same problem.
>>
>> Can anyone offer any guidance? I’m desperate as our tournament is in 6
>> days.
>>
>> Thanks,
>> Rosanna Okada
>> Lego my Eggo
>> Sent from my iPhone
>>
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