CJIT balance not displayed

[jvsena42]

On receiving CJIT, the channel is displayed as open and LN QR code is visible, but the outbound balance is not displayed as spending on home

Staging electrum address (fulcrum): 34.65.252.32:18483

Screen_recording_20260119_103412.webm

logs.txt

[jvsena42]

same behavior from iOS

Simulator.Screen.Recording.-.iPhone.16.-.2026-01-19.at.10.48.49.mp4

[jvsena42]

Problem Summary

After receiving a payment via CJIT (Collaborative Just-In-Time channel), the Lightning channel appears as open but the balance is not displayed on the home screen as "spending." User confirmed the payment
was made, and the issue persists even after the channel funding transaction is confirmed on-chain.

Root Cause Analysis

Critical Finding: LSP opened inbound-only channel

Full ChannelDetails (not from logs, from further debug) confirm this is an inbound-only channel:

channelValueSats = 562500 // Total channel: 562,500 sats
outboundCapacityMsat = 0 // User CAN SEND: 0 sats ← PROBLEM
inboundCapacityMsat = 555906000 // User CAN RECEIVE: ~555,906 sats
unspendablePunishmentReserve = 354 // User's locked reserve: 354 sats
isOutbound = false // Channel opened TO user (by LSP)
confirmations = 21 // Fully confirmed
isUsable = true // Channel is usable

This is NOT an LDK-node bug. LDK-node is correctly reporting the channel state:

The user has outboundCapacityMsat = 0 meaning they cannot send any sats
All 562,500 sats are on the LSP side
The user only has inbound (receiving) capacity, not spendable balance
For CJIT to work, after payment: outboundCapacityMsat should equal the payment amount (minus fees). The current state shows the CJIT payment was never pushed to the user's channel side.

Expected vs Actual CJIT Flow

Expected CJIT flow:

User creates CJIT invoice for X sats
Payer pays invoice → funds go to LSP
LSP opens channel with push_msat = X sats (pushing funds to user's side)
OR: LSP forwards payment through the channel immediately after opening
User receives PaymentReceived event with X sats
User has local balance ≈ X sats
What actually happened (per logs):

User created CJIT invoice (1 cjit entries)
LSP opened channel with push_msat = 0 (no funds pushed to user)
No payment was forwarded through the channel
No PaymentReceived event fired
User has 0 local balance - only inbound capacity
Root Cause: LSP/Blocktank Issue

The LSP (Blocktank) either:

Never received payment for the CJIT invoice - channel was opened as regular inbound channel
Received payment but didn't push funds - bug in LSP CJIT implementation
CJIT flow incomplete - payment went to LSP but wasn't forwarded to user
This is an upstream LSP issue, not an app or LDK-node bug. The app correctly displays what LDK-node reports (0 balance).

[jvsena42]

The unspendablePunishmentReserve is reserving all balance

ChannelDetails(channelId=c5494ab93daa2214cc0cc6fce9b62b4cb8756f9afdc0c56299587bd750164ded,                                                                           
    counterpartyNodeId=028a8910b0048630d4eb17af25668cdd7ea6f2d8ae20956e7a06e2ae46ebcb69fc, fundingTxo=OutPoint(txid=ed4d1650d77b589962c5c0fd9a6f75b84c2bb6e9fcc60ccc1422aa3db94a49c5, vout=0),                
    shortChannelId=54381845109866496, outboundScidAlias=7298558326865923, inboundScidAlias=17592186044416002511, channelValueSats=562500, unspendablePunishmentReserve=354,                                   
    userChannelId=134002364965952764158894957405457786439, feerateSatPer1000Weight=256, outboundCapacityMsat=0, inboundCapacityMsat=555906000, confirmationsRequired=0, confirmations=21, isOutbound=false,   
    isChannelReady=true, isUsable=true, isAnnounced=false, cltvExpiryDelta=72, counterpartyUnspendablePunishmentReserve=5625, counterpartyOutboundHtlcMinimumMsat=1,                                          
    counterpartyOutboundHtlcMaximumMsat=556521000, counterpartyForwardingInfoFeeBaseMsat=1000, counterpartyForwardingInfoFeeProportionalMillionths=1, counterpartyForwardingInfoCltvExpiryDelta=80,           
    nextOutboundHtlcLimitMsat=0, nextOutboundHtlcMinimumMsat=1, forceCloseSpendDelay=144, inboundHtlcMinimumMsat=1, inboundHtlcMaximumMsat=56250000,                                                          
    config=ChannelConfig(forwardingFeeProportionalMillionths=0, forwardingFeeBaseMsat=1000, cltvExpiryDelta=72, maxDustHtlcExposure=FeeRateMultiplier(multiplier=10000),                                      
    forceCloseAvoidanceMaxFeeSatoshis=1000, acceptUnderpayingHtlcs=false)) 

[jvsena42]

Not a bug.

On low amount invoices unspendablePunishmentReserve may reserve all inbound balance and it is not displayed on home

Screen_recording_20260119_120503.webm