How can i avoid concurrency

if a global value is writing on firebase by many user at a time then there will concurrent condition accur due to this , there is no accuracy

how can i avoid this problem?

You can create a random id for everyone.

Let firebase handle it.

either i have to set rule of firebase or set kodular blocks to fix it
and i cant create random id for everyone its mandatory i have to be updated the value of one tag by many user
when at a time many user request to update the value then there is the problem for accuracy

Upgrade firebase account then.

omg ,do you know what is concurrency control?

In simple words, a lot of users trying to access a particular server or service is called concurrency.
And to prevent server server from lagging or going down, a function is required which will establish connection only when it is not overriding the limit.