My word of advice if you plan to work with EE's is to first think about component annotations, follow rules for creating schematics and use engineering notations (prefixes) instead of scientific (1E-9) for component values. Your question is now pretty much split into two, 1. MPPT algorithm development and 2. Troubleshooting your main circuit. I would propose you move out 2. into SPICE, for example LTspice or PSpice and troubleshoot it there or just ignore the main circuit from your problem...