Testnet issue: bumping transaction gas price doesn't replace pending transaction

[mykhailohordin-lab]

Testnet issue, bumping transaction gas price doesn't replace pending transaction

There seems to be an issue on the Binance Smart Chain Testnet when attempting to replace ("bump") a pending transaction with a higher gas price.

Steps to reproduce:
Create and broadcast a transaction with a very low gas price, for example, gasPrice = 1 Wei, nonce = n.

The transaction remains pending, as expected.
On calling eth_getTransactionByHash, both blockHash and blockNumber are null, indicating that the transaction is not mined due to the low fee.
Then try to replace this transaction by sending another one with the same nonce (n) but with a higher gas price, for example, gasPrice = 5 GWei.

The replacement transaction is broadcast successfully, but it still never gets included in a block it stays pending indefinitely.

Expected behavior:
The second transaction (with gasPrice = 5 GWei and the same nonce) should replace the original pending one and be included in a block, as the gas price is sufficient for Testnet.

Actual behavior:
Even with a significantly higher gas price, the replacement transaction is not mined and remains pending forever.

Tx with 1 Wei gas price:
{"blockHash":null,"blockNumber":null,"from":"0x2e8d144cf1b46f08a90d1ddd64ce7d8c82e5b186","gas":"0x112ec","gasPrice":"0x1","hash":"0x039ebea406945b3d1df0d61b7d4fa38bc5a2ecd1cfc9a1bf1715817fe39eed2b","input":"0xa9059cbb00000000000000000000000047d2c5f04168d92b57a2ca74311a7512b855d5d80000000000000000000000000000000000000000000000000000000000000001","nonce":"0x30","to":"0x9250e5f20b75ba41172b47a4d5f2f6daa15af23d","transactionIndex":null,"value":"0x0","type":"0x0","chainId":"0x61","v":"0xe6","r":"0x79ae383a08e73add22bfc1d35d2954b7318532337b1057c92217a238effe1bb6","s":"0x345d81bd8a02c2ecd9de1f7281dd42dca229185a0cb8f4da628cc4688b60f160"}

Tx with 5 GWei gas price (same nonce):
{"blockHash":null,"blockNumber":null,"from":"0x2e8d144cf1b46f08a90d1ddd64ce7d8c82e5b186","gas":"0xf9ee","gasPrice":"0x12a05f200","hash":"0xd70c9860bdffdcc15095e69c2c78861310296d7c8e64af8a041f854ceb9725ee","input":"0xa9059cbb00000000000000000000000047d2c5f04168d92b57a2ca74311a7512b855d5d80000000000000000000000000000000000000000000000000000000000000001","nonce":"0x30","to":"0x9250e5f20b75ba41172b47a4d5f2f6daa15af23d","transactionIndex":null,"value":"0x0","type":"0x0","chainId":"0x61","v":"0xe5","r":"0x5fd2d10202d2cfc3137525e1e11f8620581ccfeb28799f0bc3b5368c13558daa","s":"0x4ed375dfd9f0498fee38c0f7169c9d5e1767bc9c1bda0948ffa6675098ad53d5"}