Deploy fail with command netlify-lambda build api && nuxt build

I have a nuxtjs website with netlify functions.
It has been deployed successfully hundreds of time with this netlify.toml file:

[build]
  publish = "dist"
  command = "netlify-lambda build api && nuxt build"
  functions = "./functions"

Now suddenly the deploy fails with this log:

type or past9:20:48 PM: $ netlify-lambda build api && nuxt build
9:20:49 PM: netlify-lambda: Building functions
9:20:51 PM: ModuleNotFoundError: Module not found: Error: Can't resolve 'npm install' in '/opt/build/repo/api'
    at factory.create (/opt/build/repo/node_modules/webpack/lib/Compilation.js:925:10)
9:20:51 PM:     at factory (/opt/build/repo/node_modules/webpack/lib/NormalModuleFactory.js:401:22)
9:20:51 PM:     at resolver (/opt/build/repo/node_modules/webpack/lib/NormalModuleFactory.js:130:21)
9:20:51 PM:     at asyncLib.parallel (/opt/build/repo/node_modules/webpack/lib/NormalModuleFactory.js:224:22)
9:20:51 PM:     at /opt/build/repo/node_modules/neo-async/async.js:2830:7
9:20:51 PM:     at /opt/build/repo/node_modules/neo-async/async.js:6877:13
9:20:51 PM:     at normalResolver.resolve (/opt/build/repo/node_modules/webpack/lib/NormalModuleFactory.js:214:25)
9:20:51 PM:     at doResolve (/opt/build/repo/node_modules/enhanced-resolve/lib/Resolver.js:213:14)
9:20:51 PM:     at hook.callAsync (/opt/build/repo/node_modules/enhanced-resolve/lib/Resolver.js:285:5)
9:20:51 PM:     at _fn0 (eval at create (/opt/build/repo/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:15:1)
9:20:51 PM:     at resolver.doResolve (/opt/build/repo/node_modules/enhanced-resolve/lib/UnsafeCachePlugin.js:44:7)
9:20:51 PM:     at hook.callAsync (/opt/build/repo/node_modules/enhanced-resolve/lib/Resolver.js:285:5)
9:20:51 PM:     at _fn0 (eval at create (/opt/build/repo/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:15:1)
9:20:51 PM:     at hook.callAsync (/opt/build/repo/node_modules/enhanced-resolve/lib/Resolver.js:285:5)
9:20:51 PM:     at _fn0 (eval at create (/opt/build/repo/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:27:1)
9:20:51 PM:     at resolver.doResolve (/opt/build/repo/node_modules/enhanced-resolve/lib/DescriptionFilePlugin.js:67:43)
9:20:51 PM: resolve 'npm install' in '/opt/build/repo/api'
9:20:51 PM:   Parsed request is a module
9:20:51 PM:   using description file: /opt/build/repo/package.json (relative path: ./api)
9:20:51 PM:     resolve as module
9:20:51 PM:       /opt/build/repo/api/node_modules doesn't exist or is not a directory
      /opt/build/node_modules doesn't exist or is not a directory
      /opt/node_modules doesn't exist or is not a directory
      /node_modules doesn't exist or is not a directory
      looking for modules in /opt/build/repo/node_modules
9:20:51 PM:         using description file: /opt/build/repo/package.json (relative path: ./node_modules)
9:20:51 PM:           using description file: /opt/build/repo/package.json (relative path: ./node_modules/npm install)
9:20:51 PM:             no extension
9:20:51 PM:               /opt/build/repo/node_modules/npm install doesn't exist
            .wasm
9:20:51 PM:               /opt/build/repo/node_modules/npm install.wasm doesn't exist
            .mjs
9:20:51 PM:               /opt/build/repo/node_modules/npm install.mjs doesn't exist
            .js
9:20:51 PM:               /opt/build/repo/node_modules/npm install.js doesn't exist
            .json
9:20:51 PM:               /opt/build/repo/node_modules/npm install.json doesn't exist
            .ts
9:20:51 PM:               /opt/build/repo/node_modules/npm install.ts doesn't exist
            as directory
9:20:51 PM:               /opt/build/repo/node_modules/npm install doesn't exist
​
9:20:51 PM: ────────────────────────────────────────────────────────────────
9:20:51 PM:   "build.command" failed                                        
9:20:51 PM: ────────────────────────────────────────────────────────────────
9:20:51 PM: ​
9:20:51 PM:   Error message
9:20:51 PM:   Command failed with exit code 1: netlify-lambda build api && nuxt build
9:20:51 PM: ​
9:20:51 PM:   Error location
9:20:51 PM:   In build.command from netlify.toml:
9:20:51 PM:   netlify-lambda build api && nuxt build
9:20:51 PM: ​
9:20:51 PM:   Resolved config

What can be the reason?

I wonder why you’re using netlify-lambda. You don’t need it in most cases anymore.