Unexpected NaN values in double array during backtesting

I am encountering a perplexing issue where NaN (Not-a-Number) values appear in a double[] array during backtesting in cTrader. This issue seems to be index-specific and I am seeking insights or suggestions to resolve it.

To elaborate, I am assigning numerical data to elements of a double[] array within my cBot strategy. However, I consistently observe that values assigned to certain array indices become NaN during backtesting.

Interestingly, when I use the same data and assign it to a different array index, the value is correctly stored and does not become NaN. Conversely, if I take data that works fine at a non-problematic index and assign it to one of the problematic indices, it does become NaN.

This issue is not isolated to complex code. I have reproduced the NaN behavior using a very simple test cBot with minimal code, which rules out errors in my strategy logic.

Furthermore, the NaN occurrence is not limited to a specific index range. I have observed it at various indices, and there does not appear to be any discernible pattern to the affected indices.

The problem persists across different backtests and even when testing with different market data. This suggests the issue is not data-dependent or market-specific.

Has anyone else experienced a similar index-specific NaN issue when working with arrays in cTrader backtesting? Any advice on potential causes or troubleshooting steps would be greatly appreciated.

Thank you for your time and assistance.

Apologies if the phrasing sounds unnatural, as this question has been translated from Japanese.

Sincerely,