Hi Karen,
Thanks, but I guess my issue is little deeper.
Maybe for better understanding Iâll describe in details what Iâm working on.
Via broadcast-webhook different users are asked a question with choices - numbers from 0 to 6(0, 1, 2, 3, 4, 5, 6).
Bot sums their answers and stores this sum in global attribute. User 1 chose â4â, user 2 chose â5â = 4+5= 9
Also I gave users ability to check the sum to the current time.
User checks sum and gets âcurrent sum is 9â (new flow: get attribute + send message with value).
Answers(though Iâm not confident how to set this right - maybe its the key, donât know) and sum are made global.
Now the tricky part.
I want to give user ability to change his answer and update the sum globally.
How I see it:
In the new flow I ask user: âHave you changed your mind? Give, please, new answerâ and again choices with numbers from 0 to 6.
Now bot subtracts ânew answerâ - âold answerâ and adds result to âold sumâ = ânew sumâ.
And here is the problem: bot sees last entered âold answerâ - he takes ânew answerâ from current user and subtracts âold answerâ from last answer given. So sum update canât be made correctly 
Also there is problem #2 : values donât want to be counted - I get values like â8+(1-5)â. It should be 4 though.
Would be extremely greatful to you if you help.
Kind regards