After having a look into the admin and the db, I see that there is really a lack of recurrence_number. I don't know why. In all my installations this is always.
So I propose to choose in JEM>settings>global parameters>clean db when uninstalling=yes.
and then to uninstall all JEM extensions via extensions manager.
Then install JEM with an original package from this site or from JED.
was this a new install or the continuation of your try to change from JEM 3.0.4 to JEM 2.2.2?
on JEM 2.3.0 stable in latest Joomla (3.9.22) Protostar php7.4.5
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