Z 246 Right side not going Forward

[Jkingfish55]

This unit is a Z 246, 2018 mdl., while under warranty, I sent it in for repair of the same issue. It was sent in for repairs through Lowe's, that is where I purchased it, when it came back, no one would/could tell me what was done to resolve the issue. It work fine for sometime, now, I have the same issue. I've checked and insured the belt tensioner moves freely and not binding at all. What would be the most likely problem for me to address?

 

[StarTech]

I have seen the tensioner arm for the drive belt to seize on these mower and cause problem with belt slippage but being the right side may not be the problem but worth checking anyways.

Items 7,8, and 20 in the image.

 

[Jkingfish55]

I have seen the tensioner arm for the drive belt to seize on these mower and cause problem with belt slippage but being the right side may not be the problem but worth checking anyways.

Items 7,8, and 20 in the image.
View attachment 59650

It was checked, working fine. I'm just not understanding why one side but not the other. Linkages look fine, virtually the same on both sides.