Well lemme try
You do both payments one after the other and your wallet immediately shows both Payment A and Payment B as pending. After an hour you refresh your wallet Payment A is still pending but Payment B is gone It's no longer in your pending transactions list and it is not your confirmed transactions or balance.
At this point, it was rejected by the miners and subsequently dropped from the mempool by the nodes because of it's fee being lower that the acceptable fee. As congestion increases lower fee transaction can be dropped by the nodes inorder to make room for higher fees transactions coming into the mempool and that's exactly the case with your transaction. You did not see it in your pending list because it's no longer on the mempool and your wallet has not re-synced for it to appear in your balance.
After refreshing your network on your phone the 0.05BTC you tried to send for Payment B reappeared in your wallet balance making it look like it was never spent You're a bit confused thinking probably there was a network glitch. Then you resend Payment B with a higher fee than before and it says pending immediately.
At this points your wallet has synched and the funds the funds dropped back into your wallet address as UTXO since it was rejected by the miners and you had to set the accurate fee and rebroadcast it again.
After an hour You check again.
Payment A is still pending
The resent Payment B is also still pending
Your wallet balance still reflects the 0.05BTC for the resent Payment B as if it's still available even though your wallet says pending.
At this juncture, your wallet has not re-synced, and that's why you still see it as though it's still available but in reality, it's not.