A transaction ID is calculated as the hash over the identity and a 14 byte nonce.
This means that for each identity, you can submit up to 2^112 transactions, and since the hash is SHA256 then the output is 256 bits, so every Fabric Blockchain can store up to 2^256 transactions. Keep in mind that you'll likely to run out of disk space (or money) before that.
Note that this is for each channel and not across different channels.
As for your error - try looking at the logs of the peer, maybe there is some kind of problem.