Wallet no longer shows Bitcoin balance I checked my wallet (Monarch wallet) about a week ago and I had a small amount of bitcoin in  it. I looked at it again a few days ago and it had vanished. I tried recovery, uninstalled wallet and reinstalled, but no luck. 

I have been in contact with Monarch support, they say the coin is there, but they have run out of ideas on how to recover. Is there anything I myself can do to recover my wallet, without needing the help of the wallet's support team?
If you are using some wallet software and it ceases to function for you, then you can attempt to recover your wallet using different software. This is of course only possible for wallets which you have complete control over (which means you control the private keys, not custodial accounts where some service provider controls your keys). You can attempt recovery by importing your private keys themselves into new software, or more commonly, you can recover the wallet by using your BIP39 mnemonic seed phrase (usually 12 or 24 words). This seed phrase has become an industry standard, so as long as the wallet you currently use utilizes BIP 39, you should have no problem finding some new wallet software you can perform the recovery with. 

Note that the wallet will derive your private keys and bitcoin addresses from the mnemonic seed phrase, and there are many possible derivation paths available. BIP 44/49/84 define standard paths, but there is a possibility the wallet you use will use a non-standard path. In that case, you will need to find out what path was used, and then find some software that will allow you to define a custom derivation path.