I heard that after 72 hours it gets cancelled? but the wallet seems to be rebroadcasting it every time I check..
It's just an estimate. The time it takes for a transaction to be dropped by all of the nodes is different (no specific time since someone can rebroadcast it to the network and make it stay longer).
or they say my tx is invalid?
It's because it has been dropped by most nodes (take note, not all of the nodes). I've tried to view it on most explorers and only found it here:
https://btc.com/63e0cf1edc2eff3c7af8280b1cdd5ab0cc6326ca8144d7a5e65f55af8c632350Can someone help me out? is there an alternate way out of this?
My txid is 63e0cf1edc2eff3c7af8280b1cdd5ab0cc6326ca8144d7a5e65f55af8c632350 if it helps. thanks in advance
Since the fee is way to low, it would be best to just wait for it to be gone from the mempool (completely) and should see the funds back in your address in few days (as if you never sent that transaction).