Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the use in this Registration Statement on Form S-1, of our report dated May 6, 2021, relating to the consolidated balance sheets of Forum Merger III Corporation as of December 31, 2020 and 2019, and the related consolidated statements of operations, changes in stockholders’ equity and cash flows for the year ended December 31, 2020 and for the period from June 25, 2019 (inception) through December 31, 2019, and to the reference to our Firm under the caption “Experts” in the Prospectus.