Field length update does not work

Question

ArcGIS Pro 2.8.1

I have a feature class in which I expanded a text field of lenght 100 to 255 using:

data - fields - click 'lenght' field and overwrite '100'  with '255', click save.

seems ok:

however as soon as the string gets longer than 100 chars I get an error:

Saving, exiting and restarting Pro does not help. What do I miss here?

Regards,

Bert

JayantaPoddar · Accepted Answer

According to Modifying Field Properties , If your table or feature class does not contain data, you can increase or decrease the value of Field Length.

In case you have data (rows) in the table, you add a new Field (Field Length=255). Use Field Calculator (if you need to get the values of old field to new field). Delete the old field.