I suspect that the freewheel cog is 3/32", the fixed cog is 1/8" and the chain is 3/32”.
Replace the chain with a 1/8” and it will work on both the fixed and free cogs.
You can keep the road (3/32”) crankset, it will work with 1/8" chain too.
@yoav started
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I suspect that the freewheel cog is 3/32", the fixed cog is 1/8" and the chain is 3/32”.
Replace the chain with a 1/8” and it will work on both the fixed and free cogs.
You can keep the road (3/32”) crankset, it will work with 1/8" chain too.