It is important to understand that the error is occurring probably because something is "out of bounds". In such cases, the culprit is an ARRAY
1. First locate the cell in the Report RDL where this textbox is located
2. Find the textbox's corresponding report column in report's AL code
3. Now search the first parameter of this column in the whole AL code. See which places it has been used. There will be a place/loop/trigger which makes it run in a repetitive manner
4. The error is occurring because the data that is being fed in this array is more than that array could handle with it's present dimensions
5. See if you can place a debugger inside this loop and see why this array is being fed an extra morsel when it was not designed to digest any extra. In most cases, it happens as the developer may have restructured the custom code, with no attention to proper testing.
6. If it is becoming very tedious and urgent, try increasing the culprit array's dimension & see where you land thereafter. I won't recommend to take this approach as a permanent solution, as it will again some day rise and bite you
