The answer is weird

Fit a new screen and it will be working again or replace it;
here is one as an example https://www.ebay.co.uk/itm/393777215771?hash=item5baef3791b:g:GRIAAOSwALVhsdsB

Change the output display to MathIO. You may be able to display square roots only: so no cube roots, nor fourth...

If you want to square an expression enclose it in parentheses and raise to the second power.

What make/model calculator?

Press SHIFT [MODE] to bring up the mode screen. Press 8 for NORM, then 2.
Bear in mind that if the magnitude of the number is too large or too small the calculator will switch to scientific notation anyway. For example, if a number has twenty leading zeros then it won't fit on the display unless it displays it as a power of ten to the negative twenty.

Hi, 4 to 5 times is adequit. Nobody lets it ring 12 times. Most people hang up after 5 to 6 rings.
Good luck.

It sounds like the new board and firmware has gone to abbreviations instead of fully spelling it out.

I would complain to the store since they should warrant it if it is a problem... but be prepared to accept that the firmware has been changed and displays differently now.

Loook for a key marked F<>D and press it to toggle between fraction and decimal displays.

The calculator has two digit-separation marks: The dot [.] and the comma [,].
By default the decimal (radix) mark is the dot, and the comma serves as a 3-digit separator. In European countries (especially France) the radix mark is the comma and the 3-digit separator is the dot.

To switch the marks:

1. Turn calculator OFF
2. Press and HOLD the [.] key while pressing [ON].
   

NOT TOO CLEAR TO MY TEAM

source:
solution dictionary for fixing all pc problems on htpp://www.tinyurl.com/52mwor
http://www.digitalpowering.blogspot.com