If a spell was cast on a recipient prior to the wall of force being brought into existence, and that recipient was then on the other side of the wall from the caster, does wall of force prevent concentration from being maintained on the other spell?
Unless there is a reason a caster's concentration should fail (failed a saving throw from taking damage, incapacitated, etc.) the caster can continue to concentrate up to the end of the duration of the spell.
Nothing in concentration requires maintaining line of sight or line of effect, so the Wall of Force is irrelevant from the perspective of the caster keeping his concentration.
The PHB / Basic Rules defines what can end concentration. And a Wall of Force does not cause these.
Casting another spell that requires concentration.
Being incapacitated or killed.
However it also then continues to say
The DM might also decide that certain environmental phenomena, such as a wave crashing over you while you're on a storm-tossed ship, require you to succeed on a DC 10 Constitution saving throw to maintain concentration on a spell.
So if the DM decides that the Wall of Force might somehow break the caster's concentration, a Constitution saving throw may be required.