Hello Martians
Here are RPCs you can use if you have issues.
To change RPC simply open your Metamask go to / Networks / Add Network.
Then tape in any of the following RPCs
I) OFFICIAL H1 RPC (frequently inoperable, yet still usable when the network isn’t too busy)
Network Name : Harmony Mainnet
New RPC URL : https://api.harmony.one/
Chain ID: 1666600000
Currency Symbol: ONE
Block Explorer URL : https://explorer.harmony.one/
II) POKT RPC (second by lvl of congestion RPC)
Network Name : Harmony Mainnet 0 POKT Portal
New RPC URL : https://harmony-0-rpc.gateway.pokt.network/
Chain ID: 1666600000
Currency Symbol: ONE
Block Explorer URL : https://explorer.harmony.one/
III) FUZZ RPC
Network Name : Harmony Fuzz
New RPC URL : https://api.fuzz.fi/
Chain ID: 1666600000
Currency Symbol: ONE
Block Explorer URL : https://explorer.harmony.one/
IV) ONECHAIN RPC
Network Name : ONEChain RPC
New RPC URL : https://rpc.onechain.services/
Chain ID: 1666600000
Currency Symbol: ONE
Block Explorer URL : https://explorer.harmony.one/
V) HARMONY FOXNET
Network Name : Harmony Foxnet
New RPC URL : https://rpc.foxswap.fi
Chain ID: 1666600000
Currency Symbol: ONE
Block Explorer URL : https://explorer.harmony.one/
VI ) Hermes RPC
Network Name: Hermes DeFi RPC
RPC URL: https://rpc.hermesdefi.io/
Chain ID: 1666600000
Currency Symbol: ONE
Block Explorer: https://explorer.harmony.one/