OPT9221: Vertical lines in OPT9221

Hi, we've developed a custom board with the OPT8241 sensor and the OPT9221 controller and we're receiving the image with some vertical lines. After reading some forums, it seems that maybe these lines can be caused by a DDR timing. Due to semiconductors shortage, we can't include the recommended DDR in our design. We have run the phy test and mac test (the results are attached), we believe that the mac test isn't totally correct and DDR can be an issue. Could you give us some hint how to evaluate if the DDR is working fine or what other issue can cause these vertical lines?

Thanks