Fulljack

Thank you very much PsyClown for your honest answer. I will return the TOBO back to the supplier.
Fulljack

@Fulljack Next time rather post directly on the forum instead of uploading a word document.
 
I do not feel or believe one needs to have comms between the battery and inverter for the battery to perform correctly - the BMS is integrated and still active, even without a comms cable. If you use the incorrect current or voltage, the BMS should kick in and make sure nothing funky or dangerous happens.
 
Your battery capacity dropping is a concern and to me that seems like its either a cell which is not happy or the BMS is being a bit wonky. Also the cells are not balanced, cell 7 is practically full while the others are not. There is a big difference between the highest voltage cell and the lowest voltage cell.
This is likely part of the cause to the issues you are experiencing, the BMS is stopping charge when one of the cells (likely #7) is reaching its limit and therefore it does not allow for the other cells to charge fully. I am going to take a guess and assume that the BMS does not have an active balancer, it might have a passive balancer but if so it is likely a very small, low current one so will take a long time to balance.
 
I do not know these ToBo batteries but if getting a different inverter (or just battery) is an option, it may not be a bad one. Alternatively, if you are up for it and feel you are competent enough you could take it apart and change the BMS - warranty would be void though.
Alternatively, perhaps take it back to the supplier - there might be a bug in the firmware and a firmware update could resolve the issue otherwise they might swap it out with a new battery which will hopefully have the cells more balanced and prevent the issues you are experiencing from happening.
 
I do not see your inverter causing these issues. I feel it is 100% the battery.
I see it is a practically brand new battery, if it were me I'd return it if possible and buy a different battery brand.