Steps to reproduce:

* Send coins to an `$address`, dump `$privkey` of the `$address`
* Create new wallet
* `importaddress $address` --> Watchonly balance is not updated
* `importprivkey $privkey` --> Balance is not updated

Needs a restart to get fixed. See also #11477 
{
    UniValue warnings(UniValue::VARR);
    const std::string& descriptor = data["desc"].get_str();
    FlatSigningProvider keys;
    std::string error;
    auto parsed_desc = Parse(descriptor, keys, error, /* rue);
    if (!parsed_desc) {
        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, error);
    }
    if (parsed_desc->GetOutputType() == OutputType::BECH32M) {
        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Bech32m descriptors cannot be imported into legacy wallets");
    }
    have_solving_data = parsed_desc->IsSolvable();
    const bool watch_only = data.exists("watchonly") ? data["watchonly"].get_bool() : false;
    int64_t range_start = 0, range_end = 0;
    if (!parsed_desc->IsRange() && data.exists("range")) {
        throw JSONRPCError(RPC_INVALID_PARAMETER, "Range should not be specified for an un-ranged descriptor");
    } else if (parsed_desc->IsRange()) {
        if (!data.exists("range")) {
            throw JSONRPCError(RPC_INVALID_PARAMETER, "Descriptor is ranged, please specify the range");
        }
        std::tie(range_start, range_end) = ParseDescriptorRange(data["range"]);