Drive Problems

I was testing my drive,but my drive kept going right not straight. It would go --------- then just|
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how do I make it just go straight.
Also all drive motors are strength.
Here’s the Program.

check for friction on one side or bent axles.

No code was posted. Try again

It might be that the internal gearing is faster with one motor. I know this might be the problem because we had the same issue.