That was the issue, Thank you.
For anyone in the future that might read this:
In the Core Lighting web UI, goto channel details there is a "Spendable" amount. Make sure this reads as greater than zero. Which is different from "Maximum Send" amount which shows your whole channel size balance. ( not reflecting the reserve amount)
If you own the two nodes, the keysend is key to maintain some kind of balance in the channel and avoid this problems.
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