min Relay Fee Not Met

[Schnema1]

CLN 24.09
RTL 0.15.4

Error 1:
Error Broadcasting Transaction: Error Code: -26\nerror Message:\nmin Relay Fee Not Met, 274 < 281. Unsent Tx Discarded 0200xxxxxxx

Error 2:
They Sent Error Channel 0ee2c1e1e6xxxxx: Number Of Pending Channels Exceed Maximum

Recently I did want to complete lighting swaps after some while. As usual RTL > Peers > Add Peer > Enter Pub key, set amount and this time I choose feerate "normal". Usually I set it to custom and enter a value little higher than mempool. But not lower than 1 stat/vByte. However, I got immediately error 1. If I retry, then I get error 2.

Channel state is Disconnected and Pending. Same for the second swap attempt with another node.

Findings:

• Onchain funds are not marked as reserved.
• Channel partner wrote he can see my attempt.
• But funding transaction is not in mempool.space

How to proceed?

I saw in CLN documentation fundchannel_cancel This seems to be risky but as funds are not reserved and no fundingTx in mempool a possible solution.
Also openchannel_abort seems to be a solution.

May please someone assist me in solve the problem?
If possible to explain or point me where to read, why this can happen and how I can avoid this in future.

[Schnema1]

Ok, as nobody helped me, time did.

Anyone stumbeling across this topic. Here is the solution and the reason.

TL;DR;

Related only to Bitcoin Core V29.0 and probably before

• Check if funding transaction is not broadcasted
• Start node in developer mode
• forget channel
• Tell the channel partner to delete your request too.

Reason:
As assumed correctly, it was an fee error. So RTL suggested me 1 sat/vbyte what I choose this time. Usually I enter the value by hand. However, the fee seemed to low for my bitcoin core client. In version 29 the min. fee was default 1sat/vbyte. As I did not mention any other value in the bitcoin.conf file, a fee lower than 1 would be rejected. This is exactly what happened.
The problem was within lightning, as it registered the channel opening in the database. But as the bitcoin node refused the funding tx, it was never broadcasted. Thus, starting the lightning node in dev mode and remove the channel data manually, solved the problem. But I still could not connect to channel partner.
So the owner needed to "lncli abandonchannel" to solve the issue.