Please help us help you and fill where relevant:
Your LimeSurvey version: Versión 4.3.31+201214
Own server or LimeSurvey hosting: Own server
Survey theme/template: Bootwatch
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Dear all, 

I'm working on my survey and I cannot add or change some question conditions. I can edit it but then after some time they go back to the previous condition or to blank if no condition was set before. This happens if I do it manually (expression script, as I usually do) and if I use the condition manager.

It's a behaviour I've seen in other surveys before but this time is critical and I cannot continue without editing some conditions. 

Has someone observed this before? I couldn't find any similar problem in the forum. Is it solved in the version 5 (I'll change to the newest version ASAP) ??.

Thanks for your help

I have not experienced that in5.x. I suggest updating for that and many other reasons.

Like Tony says, update to the latest LS5.x.

Versión 4.3.31+201214

In my point of view, LS4 was never stable for productive use and was then substituted by LS5.

Your version of Limesurvey is 1,5 years old, and hasn't received any bug fixes or security updates since the end of 2020.

As Tony, I do not experience any of the described issues in LS5. You should update.

Thanks, it seems the problem is solved in 5.3 version.